

<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.unisys.com/role/AccountingStandards" xlink:href="uis-20180930.xsd#AccountingStandards" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/AccountingStandardsDetail" xlink:href="uis-20180930.xsd#AccountingStandardsDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/AccountingStandardsTables" xlink:href="uis-20180930.xsd#AccountingStandardsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncome" xlink:href="uis-20180930.xsd#AccumulatedOtherComprehensiveIncome" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeAmountsReclassifiedOutOfAccumulatedOtherComprehensiveIncomeDetail" xlink:href="uis-20180930.xsd#AccumulatedOtherComprehensiveIncomeAmountsReclassifiedOutOfAccumulatedOtherComprehensiveIncomeDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeDetail" xlink:href="uis-20180930.xsd#AccumulatedOtherComprehensiveIncomeDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeNoncontrollingInterestsDetail" xlink:href="uis-20180930.xsd#AccumulatedOtherComprehensiveIncomeNoncontrollingInterestsDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeTables" xlink:href="uis-20180930.xsd#AccumulatedOtherComprehensiveIncomeTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/BasisOfPresentation" xlink:href="uis-20180930.xsd#BasisOfPresentation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/CommitmentsAndContingencies" xlink:href="uis-20180930.xsd#CommitmentsAndContingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/CommitmentsAndContingenciesAdditionalInformationDetail" xlink:href="uis-20180930.xsd#CommitmentsAndContingenciesAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/ConsolidatedBalanceSheetsUnaudited" xlink:href="uis-20180930.xsd#ConsolidatedBalanceSheetsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/ConsolidatedBalanceSheetsUnauditedParenthetical" xlink:href="uis-20180930.xsd#ConsolidatedBalanceSheetsUnauditedParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/ConsolidatedStatementsOfCashFlowsUnaudited" xlink:href="uis-20180930.xsd#ConsolidatedStatementsOfCashFlowsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/ConsolidatedStatementsOfComprehensiveIncomeUnaudited" xlink:href="uis-20180930.xsd#ConsolidatedStatementsOfComprehensiveIncomeUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/ConsolidatedStatementsOfComprehensiveIncomeUnauditedParenthetical" xlink:href="uis-20180930.xsd#ConsolidatedStatementsOfComprehensiveIncomeUnauditedParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/ConsolidatedStatementsOfDeficitUnaudited" xlink:href="uis-20180930.xsd#ConsolidatedStatementsOfDeficitUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/ConsolidatedStatementsOfIncomeUnaudited" xlink:href="uis-20180930.xsd#ConsolidatedStatementsOfIncomeUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/CostReductionActions" xlink:href="uis-20180930.xsd#CostReductionActions" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/CostReductionActionsAdditionalInformationDetail" xlink:href="uis-20180930.xsd#CostReductionActionsAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/CostReductionActionsIndividualComponentsOfWorkForceReductionAndIdleLeaseCostDetail" xlink:href="uis-20180930.xsd#CostReductionActionsIndividualComponentsOfWorkForceReductionAndIdleLeaseCostDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/CostReductionActionsTables" xlink:href="uis-20180930.xsd#CostReductionActionsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/Debt" xlink:href="uis-20180930.xsd#Debt" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/DebtAdditionalInformationDetail" xlink:href="uis-20180930.xsd#DebtAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/DebtScheduleOfComponentsOfLongTermDebtDetails" xlink:href="uis-20180930.xsd#DebtScheduleOfComponentsOfLongTermDebtDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/DebtScheduleOfInterestExpenseDetails" xlink:href="uis-20180930.xsd#DebtScheduleOfInterestExpenseDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/DebtTables" xlink:href="uis-20180930.xsd#DebtTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/DocumentAndEntityInformation" xlink:href="uis-20180930.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/EarningsPerShare" xlink:href="uis-20180930.xsd#EarningsPerShare" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/EarningsPerShareComputationOfEarningsLossPerCommonShareAttributableToUnisysCorporationDetail" xlink:href="uis-20180930.xsd#EarningsPerShareComputationOfEarningsLossPerCommonShareAttributableToUnisysCorporationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/EarningsPerShareTables" xlink:href="uis-20180930.xsd#EarningsPerShareTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurements" xlink:href="uis-20180930.xsd#FinancialInstrumentsAndFairValueMeasurements" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsAdditionalInformationDetail" xlink:href="uis-20180930.xsd#FinancialInstrumentsAndFairValueMeasurementsAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsFairValueOfForeignExchangeForwardContractsByBalanceSheetLocationDetails" xlink:href="uis-20180930.xsd#FinancialInstrumentsAndFairValueMeasurementsFairValueOfForeignExchangeForwardContractsByBalanceSheetLocationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsFairValuesOfOtherFinancialInstrumentsNotMeasuredAtFairValueInConsolidatedBalanceSheetsDetails" xlink:href="uis-20180930.xsd#FinancialInstrumentsAndFairValueMeasurementsFairValuesOfOtherFinancialInstrumentsNotMeasuredAtFairValueInConsolidatedBalanceSheetsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsGainsAndLossesRecognizedOnForeignExchangeForwardContractsDetails" xlink:href="uis-20180930.xsd#FinancialInstrumentsAndFairValueMeasurementsGainsAndLossesRecognizedOnForeignExchangeForwardContractsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsTables" xlink:href="uis-20180930.xsd#FinancialInstrumentsAndFairValueMeasurementsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/Goodwill" xlink:href="uis-20180930.xsd#Goodwill" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/GoodwillDetails" xlink:href="uis-20180930.xsd#GoodwillDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/GoodwillScheduleOfChangesInCarryingAmountOfGoodwillBySegmentDetails" xlink:href="uis-20180930.xsd#GoodwillScheduleOfChangesInCarryingAmountOfGoodwillBySegmentDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/GoodwillTables" xlink:href="uis-20180930.xsd#GoodwillTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/IncomeTaxes" xlink:href="uis-20180930.xsd#IncomeTaxes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/IncomeTaxesDetails" xlink:href="uis-20180930.xsd#IncomeTaxesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/PensionAndPostretirementBenefits" xlink:href="uis-20180930.xsd#PensionAndPostretirementBenefits" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/PensionAndPostretirementBenefitsAdditionalInformationDetail" xlink:href="uis-20180930.xsd#PensionAndPostretirementBenefitsAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/PensionAndPostretirementBenefitsComponentsOfNetPeriodicBenefitExpenseDetail" xlink:href="uis-20180930.xsd#PensionAndPostretirementBenefitsComponentsOfNetPeriodicBenefitExpenseDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/PensionAndPostretirementBenefitsTables" xlink:href="uis-20180930.xsd#PensionAndPostretirementBenefitsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/Properties" xlink:href="uis-20180930.xsd#Properties" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/PropertiesDetails" xlink:href="uis-20180930.xsd#PropertiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SegmentInformation" xlink:href="uis-20180930.xsd#SegmentInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SegmentInformationAdditionalInformationDetail" xlink:href="uis-20180930.xsd#SegmentInformationAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SegmentInformationCustomerRevenueByClassesOfSimilarProductsOrServicesDetail" xlink:href="uis-20180930.xsd#SegmentInformationCustomerRevenueByClassesOfSimilarProductsOrServicesDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SegmentInformationReconciliationOfSegmentOperatingIncomeToConsolidatedLossBeforeIncomeTaxesDetail" xlink:href="uis-20180930.xsd#SegmentInformationReconciliationOfSegmentOperatingIncomeToConsolidatedLossBeforeIncomeTaxesDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SegmentInformationRevenuePropertiesAndOutsourcingAssetsByGeographicSegmentDetail" xlink:href="uis-20180930.xsd#SegmentInformationRevenuePropertiesAndOutsourcingAssetsByGeographicSegmentDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SegmentInformationSummaryOfOperationsBySegmentDetail" xlink:href="uis-20180930.xsd#SegmentInformationSummaryOfOperationsBySegmentDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SegmentInformationTables" xlink:href="uis-20180930.xsd#SegmentInformationTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/StockCompensation" xlink:href="uis-20180930.xsd#StockCompensation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/StockCompensationAdditionalInformationDetail" xlink:href="uis-20180930.xsd#StockCompensationAdditionalInformationDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/StockCompensationStockCompensationWeightedAverageAssumptionsDetails" xlink:href="uis-20180930.xsd#StockCompensationStockCompensationWeightedAverageAssumptionsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/StockCompensationSummaryOfRestrictedStockUnitActivityDetail" xlink:href="uis-20180930.xsd#StockCompensationSummaryOfRestrictedStockUnitActivityDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/StockCompensationSummaryOfStockOptionActivityDetail" xlink:href="uis-20180930.xsd#StockCompensationSummaryOfStockOptionActivityDetail" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/StockCompensationTables" xlink:href="uis-20180930.xsd#StockCompensationTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SummaryOfSignificantAccountingPolicies" xlink:href="uis-20180930.xsd#SummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SummaryOfSignificantAccountingPoliciesDetails" xlink:href="uis-20180930.xsd#SummaryOfSignificantAccountingPoliciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:href="uis-20180930.xsd#SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SupplementalCashFlowInformation" xlink:href="uis-20180930.xsd#SupplementalCashFlowInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SupplementalCashFlowInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetails" xlink:href="uis-20180930.xsd#SupplementalCashFlowInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SupplementalCashFlowInformationScheduleOfSupplementalCashFlowInformationDetails" xlink:href="uis-20180930.xsd#SupplementalCashFlowInformationScheduleOfSupplementalCashFlowInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.unisys.com/role/SupplementalCashFlowInformationTables" xlink:href="uis-20180930.xsd#SupplementalCashFlowInformationTables" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" xlink:type="simple" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccountingStandards" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccountingStandardsDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_7F62D61C7F16E3026DD8EE93B5ABCDA4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_BC38EC4308B91991F1C9EE93B5A6700D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_7F62D61C7F16E3026DD8EE93B5ABCDA4" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_BC38EC4308B91991F1C9EE93B5A6700D" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E6996CBEF0E0D8DC650AEE93B5A623D0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_BC38EC4308B91991F1C9EE93B5A6700D" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E6996CBEF0E0D8DC650AEE93B5A623D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_310CFE88410311CBA74AEE93B5A6A15D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E6996CBEF0E0D8DC650AEE93B5A623D0" xlink:to="loc_us-gaap_TypeOfAdoptionMember_310CFE88410311CBA74AEE93B5A6A15D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_310CFE88410311CBA74AEE93B5A6A15D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E6996CBEF0E0D8DC650AEE93B5A623D0" xlink:to="loc_us-gaap_TypeOfAdoptionMember_310CFE88410311CBA74AEE93B5A6A15D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201707Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201707Member_BC6FF1683815E91A5D07EE93B5A729A1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_310CFE88410311CBA74AEE93B5A6A15D" xlink:to="loc_us-gaap_AccountingStandardsUpdate201707Member_BC6FF1683815E91A5D07EE93B5A729A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member_3E6F4012B10EA98577FBEE93B5A73DED" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_310CFE88410311CBA74AEE93B5A6A15D" xlink:to="loc_us-gaap_AccountingStandardsUpdate201409Member_3E6F4012B10EA98577FBEE93B5A73DED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_823A80ED07034AF9C342EE93B5A7AB56" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_BC38EC4308B91991F1C9EE93B5A6700D" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_823A80ED07034AF9C342EE93B5A7AB56" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_6FADE2675F07A2CAB84EEE93B5A7A788_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_823A80ED07034AF9C342EE93B5A7AB56" xlink:to="loc_us-gaap_EquityComponentDomain_6FADE2675F07A2CAB84EEE93B5A7A788_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_6FADE2675F07A2CAB84EEE93B5A7A788" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_823A80ED07034AF9C342EE93B5A7AB56" xlink:to="loc_us-gaap_EquityComponentDomain_6FADE2675F07A2CAB84EEE93B5A7A788" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_6466F47B1654035B491AEE93B5A7B34A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6FADE2675F07A2CAB84EEE93B5A7A788" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_6466F47B1654035B491AEE93B5A7B34A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_C700A169C8E0BB2A5A66EE93B5A8193E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_6FADE2675F07A2CAB84EEE93B5A7A788" xlink:to="loc_us-gaap_RetainedEarningsMember_C700A169C8E0BB2A5A66EE93B5A8193E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_443E223AA1E3A69516ECEE93B5A863FB" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_BC38EC4308B91991F1C9EE93B5A6700D" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_443E223AA1E3A69516ECEE93B5A863FB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C535B61AFAA24A5D1037EE93B5A8CA69_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_443E223AA1E3A69516ECEE93B5A863FB" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C535B61AFAA24A5D1037EE93B5A8CA69_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain" xlink:label="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C535B61AFAA24A5D1037EE93B5A8CA69" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionAxis_443E223AA1E3A69516ECEE93B5A863FB" xlink:to="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C535B61AFAA24A5D1037EE93B5A8CA69" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member" xlink:label="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_1CB5E7B03DA59C9A7643EE93B5A8F32A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C535B61AFAA24A5D1037EE93B5A8CA69" xlink:to="loc_us-gaap_DifferenceBetweenRevenueGuidanceInEffectBeforeAndAfterTopic606Member_1CB5E7B03DA59C9A7643EE93B5A8F32A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member" xlink:label="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_68375BD034C3F50EA6B9EE93B5A9E2E0" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InitialApplicationPeriodCumulativeEffectTransitionDomain_C535B61AFAA24A5D1037EE93B5A8CA69" xlink:to="loc_us-gaap_CalculatedUnderRevenueGuidanceInEffectBeforeTopic606Member_68375BD034C3F50EA6B9EE93B5A9E2E0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_517F82982FFA1A3A5EC1EE93B5A9ABC7" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_BC38EC4308B91991F1C9EE93B5A6700D" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_517F82982FFA1A3A5EC1EE93B5A9ABC7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_1D601F6A583CC6A1A4DAEE93B5A98DFC_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_517F82982FFA1A3A5EC1EE93B5A9ABC7" xlink:to="loc_us-gaap_SegmentDomain_1D601F6A583CC6A1A4DAEE93B5A98DFC_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_1D601F6A583CC6A1A4DAEE93B5A98DFC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_517F82982FFA1A3A5EC1EE93B5A9ABC7" xlink:to="loc_us-gaap_SegmentDomain_1D601F6A583CC6A1A4DAEE93B5A98DFC" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ServicesMember" xlink:label="loc_uis_ServicesMember_BA0967F58881B558DB32EE93B5AA4361" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_1D601F6A583CC6A1A4DAEE93B5A98DFC" xlink:to="loc_uis_ServicesMember_BA0967F58881B558DB32EE93B5AA4361" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_65102BB6CD7BA8DBCF85EE93B5AA5D68" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_1D601F6A583CC6A1A4DAEE93B5A98DFC" xlink:to="loc_uis_TechnologyMember_65102BB6CD7BA8DBCF85EE93B5AA5D68" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis_7B134191852AD47A6C14EE93B5AABD99" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_BC38EC4308B91991F1C9EE93B5A6700D" xlink:to="loc_srt_ProductOrServiceAxis_7B134191852AD47A6C14EE93B5AABD99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_BB605026799CE360686DEE93B5AA6A90_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_7B134191852AD47A6C14EE93B5AABD99" xlink:to="loc_srt_ProductsAndServicesDomain_BB605026799CE360686DEE93B5AA6A90_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_BB605026799CE360686DEE93B5AA6A90" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_7B134191852AD47A6C14EE93B5AABD99" xlink:to="loc_srt_ProductsAndServicesDomain_BB605026799CE360686DEE93B5AA6A90" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LicenseAndMaintenanceMember" xlink:label="loc_us-gaap_LicenseAndMaintenanceMember_A38CAA009AB292612B4EEE93B5AAECB5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_BB605026799CE360686DEE93B5AA6A90" xlink:to="loc_us-gaap_LicenseAndMaintenanceMember_A38CAA009AB292612B4EEE93B5AAECB5" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect" xlink:label="loc_uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect_CD180CBBF73D70AE3EB8EE93B5AB0037" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_7F62D61C7F16E3026DD8EE93B5ABCDA4" xlink:to="loc_uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect_CD180CBBF73D70AE3EB8EE93B5AB0037" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DefinedBenefitPlanNetPeriodicBenefitCostExcludingServiceCost" xlink:label="loc_uis_DefinedBenefitPlanNetPeriodicBenefitCostExcludingServiceCost_2A7643D5E4FD7C8F8BE5EE93B5AB354C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_7F62D61C7F16E3026DD8EE93B5ABCDA4" xlink:to="loc_uis_DefinedBenefitPlanNetPeriodicBenefitCostExcludingServiceCost_2A7643D5E4FD7C8F8BE5EE93B5AB354C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption" xlink:label="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_D674330E9DFA18045F39EE93B5AB3C0F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_7F62D61C7F16E3026DD8EE93B5ABCDA4" xlink:to="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_D674330E9DFA18045F39EE93B5AB3C0F" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract" xlink:label="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_7F62D61C7F16E3026DD8EE93B5ABCDA4" xlink:to="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenuesAbstract" xlink:label="loc_us-gaap_RevenuesAbstract_2D527FAB28519646C9A0EE93B5ACE519" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_RevenuesAbstract_2D527FAB28519646C9A0EE93B5ACE519" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_953453A3754C832CB9B2EE93B5AC8330" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_2D527FAB28519646C9A0EE93B5ACE519" xlink:to="loc_us-gaap_Revenues_953453A3754C832CB9B2EE93B5AC8330" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostOfRevenueAbstract" xlink:label="loc_us-gaap_CostOfRevenueAbstract_4001EEA9BE6D1BFAC81BEE93B5AC3BCD" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_CostOfRevenueAbstract_4001EEA9BE6D1BFAC81BEE93B5AC3BCD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaap_CostOfRevenue_B043BEEF0A226511D82FEE93B5ACF78A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfRevenueAbstract_4001EEA9BE6D1BFAC81BEE93B5AC3BCD" xlink:to="loc_us-gaap_CostOfRevenue_B043BEEF0A226511D82FEE93B5ACF78A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_8CC3685FA4EABE6DA83FEE93B5ADDEFA" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_8CC3685FA4EABE6DA83FEE93B5ADDEFA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_5AE1D972DAA4D83700CEEE93B5AD58C5" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_OperatingIncomeLoss_5AE1D972DAA4D83700CEEE93B5AD58C5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_AB7303FDCDE3D962EB88EE93B5ADC30A" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_AB7303FDCDE3D962EB88EE93B5ADC30A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_C9370493FB581B329414EE93B5AD8CDC" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_C9370493FB581B329414EE93B5AD8CDC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_37AC6F89FC012D0446C7EE93B5ADBE2B" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_ProfitLoss_37AC6F89FC012D0446C7EE93B5ADBE2B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_775CBFC61E85472C6BB7EE93B5AD3DA6" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_NetIncomeLoss_775CBFC61E85472C6BB7EE93B5AD3DA6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract_78C5EC4A8446F9AF1EFEEE93B5AE3A4F" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EffectofAdoptingStandardonCompanyConsolidatedFinancialStatementsAbstract_4D77B2DA23A08827AAD8EE93B5ABB80F" xlink:to="loc_us-gaap_StatementOfFinancialPositionAbstract_78C5EC4A8446F9AF1EFEEE93B5AE3A4F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_78C5EC4A8446F9AF1EFEEE93B5AE3A4F" xlink:to="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountsNotesAndLoansReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_5D5972D682001794FF44EE93B5AEC2BD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:to="loc_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_5D5972D682001794FF44EE93B5AEC2BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ContractWithCustomerAssetNetCurrent" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetCurrent_341F122EDE35E5D26CEEEE93B5AE19AE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:to="loc_us-gaap_ContractWithCustomerAssetNetCurrent_341F122EDE35E5D26CEEEE93B5AE19AE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_34532F6327A078D64A6AEE93B5AF9097" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:to="loc_us-gaap_InventoryNet_34532F6327A078D64A6AEE93B5AF9097" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_DA770EC60A21C7C25064EE93B5AF6254" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_DA770EC60A21C7C25064EE93B5AF6254" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DeferredIncomeTaxAssetsNet" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_D85A3219DAD22CFC93C8EE93B5AF40D1" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:to="loc_us-gaap_DeferredIncomeTaxAssetsNet_D85A3219DAD22CFC93C8EE93B5AF40D1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_EBB24CFEA6DF65402927EE93B5AF2D77" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_EBB24CFEA6DF65402927EE93B5AF2D77" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_3A4F2E65CA4820C2E6E5EE93B5AFF479" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_20C9D0C2426F9EE4A9ACEE93B5AE32F8" xlink:to="loc_us-gaap_Assets_3A4F2E65CA4820C2E6E5EE93B5AFF479" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesAbstract" xlink:label="loc_us-gaap_LiabilitiesAbstract_9ABF470207645034C64BEE93B5AFD67B" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_78C5EC4A8446F9AF1EFEEE93B5AE3A4F" xlink:to="loc_us-gaap_LiabilitiesAbstract_9ABF470207645034C64BEE93B5AFD67B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent_93D7F842F14838E0DE9AEE93B5B0BF0A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_9ABF470207645034C64BEE93B5AFD67B" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityCurrent_93D7F842F14838E0DE9AEE93B5B0BF0A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent_D438FD4BCAD5D0D6023FEE93B5B0288D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_9ABF470207645034C64BEE93B5AFD67B" xlink:to="loc_us-gaap_OtherLiabilitiesCurrent_D438FD4BCAD5D0D6023FEE93B5B0288D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ContractWithCustomerLiabilityNoncurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_FF58E56CF5A817F73952EE93B5B0BC15" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_9ABF470207645034C64BEE93B5AFD67B" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_FF58E56CF5A817F73952EE93B5B0BC15" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_1994E39C32C1C9DA7A8BEE93B5B09C5D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAbstract_9ABF470207645034C64BEE93B5AFD67B" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_1994E39C32C1C9DA7A8BEE93B5B09C5D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract_CEA01836B27BB7163CE2EE93B5B0E26A" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_78C5EC4A8446F9AF1EFEEE93B5AE3A4F" xlink:to="loc_us-gaap_EquityAbstract_CEA01836B27BB7163CE2EE93B5B0E26A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_4B415B70AE1183666DDBEE93B5B15F27" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityAbstract_CEA01836B27BB7163CE2EE93B5B0E26A" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_4B415B70AE1183666DDBEE93B5B15F27" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_F7BF98C15EE0407C5EA6EE93B5B11EDD" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_78C5EC4A8446F9AF1EFEEE93B5AE3A4F" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_F7BF98C15EE0407C5EA6EE93B5B11EDD" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccountingStandardsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncome" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeAmountsReclassifiedOutOfAccumulatedOtherComprehensiveIncomeDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_FF920EFEEBD25E04A8D565DA3D779F60" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_87733605E24E57949B807F2358CAE9F2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_FF920EFEEBD25E04A8D565DA3D779F60" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_87733605E24E57949B807F2358CAE9F2" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_2304AC67B57E5A94B08AD20E61F9CEA4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_87733605E24E57949B807F2358CAE9F2" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_2304AC67B57E5A94B08AD20E61F9CEA4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_3CE057E4388CBAFBA26093D4756BE0C2_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_2304AC67B57E5A94B08AD20E61F9CEA4" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_3CE057E4388CBAFBA26093D4756BE0C2_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_3A466E21C540503D9649C81B768E79D4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_2304AC67B57E5A94B08AD20E61F9CEA4" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_3A466E21C540503D9649C81B768E79D4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_E8723B4D5F4855D28549D38CB5B28977" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_3A466E21C540503D9649C81B768E79D4" xlink:to="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_E8723B4D5F4855D28549D38CB5B28977" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_122F3314DEB25DB284B4BC2ED60B3E38" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_87733605E24E57949B807F2358CAE9F2" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_122F3314DEB25DB284B4BC2ED60B3E38" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_28E081F25F363B92DBED93D4756C4619_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_122F3314DEB25DB284B4BC2ED60B3E38" xlink:to="loc_us-gaap_EquityComponentDomain_28E081F25F363B92DBED93D4756C4619_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_70AFD534BB575532A82EE0C0F7FBD1F4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_122F3314DEB25DB284B4BC2ED60B3E38" xlink:to="loc_us-gaap_EquityComponentDomain_70AFD534BB575532A82EE0C0F7FBD1F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedTranslationAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_5BB91FFFCDBD55BC9D13823C8F70899F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_70AFD534BB575532A82EE0C0F7FBD1F4" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_5BB91FFFCDBD55BC9D13823C8F70899F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_0FF936C1DF1B564C8928ADCA37143AE5" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_70AFD534BB575532A82EE0C0F7FBD1F4" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_0FF936C1DF1B564C8928ADCA37143AE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCreditMember" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCreditMember_E472DCFD5B7058A59A6A0DE6D80E4850" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_0FF936C1DF1B564C8928ADCA37143AE5" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentNetPriorServiceCostCreditMember_E472DCFD5B7058A59A6A0DE6D80E4850" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentNetUnamortizedGainLossMember" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentNetUnamortizedGainLossMember_D7F694EF2F1056849B27A65C3E79C9CF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_0FF936C1DF1B564C8928ADCA37143AE5" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentNetUnamortizedGainLossMember_D7F694EF2F1056849B27A65C3E79C9CF" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_AccumulatedDefinedBenefitPlansAdjustmentNetCurtailmentGainLossAttributabletoParentMember" xlink:label="loc_uis_AccumulatedDefinedBenefitPlansAdjustmentNetCurtailmentGainLossAttributabletoParentMember_4005DBA1E16D519793174F24ADBB3855" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_0FF936C1DF1B564C8928ADCA37143AE5" xlink:to="loc_uis_AccumulatedDefinedBenefitPlansAdjustmentNetCurtailmentGainLossAttributabletoParentMember_4005DBA1E16D519793174F24ADBB3855" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_4F1A4BBFB22454E1B1BF3407C769C2B2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_FF920EFEEBD25E04A8D565DA3D779F60" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_4F1A4BBFB22454E1B1BF3407C769C2B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresAbstract_0BEA7B5163855F82A8937AE9216DD016" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_FF920EFEEBD25E04A8D565DA3D779F60" xlink:to="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresAbstract_0BEA7B5163855F82A8937AE9216DD016" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_76E99EC7696253F5AE0EEFA6E92FAD0B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansDisclosuresAbstract_0BEA7B5163855F82A8937AE9216DD016" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_76E99EC7696253F5AE0EEFA6E92FAD0B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAociCurrentPeriodTax" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_1CAB45D16B0A5E70AA80C20AEBEAF55E" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_FF920EFEEBD25E04A8D565DA3D779F60" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodTax_1CAB45D16B0A5E70AA80C20AEBEAF55E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_E6865ED5841B5E098D9C276500F8054D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_FF920EFEEBD25E04A8D565DA3D779F60" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_E6865ED5841B5E098D9C276500F8054D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_9283D744D73E3FE2319CE92331884456" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_329D6F9A241164BE1898E9233187CA21" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_9283D744D73E3FE2319CE92331884456" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_329D6F9A241164BE1898E9233187CA21" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_56508FF5FB9C40183CDEE92331872762" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_329D6F9A241164BE1898E9233187CA21" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_56508FF5FB9C40183CDEE92331872762" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_EEBCC4573EA45A475EF0E9233187FC4D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_56508FF5FB9C40183CDEE92331872762" xlink:to="loc_us-gaap_EquityComponentDomain_EEBCC4573EA45A475EF0E9233187FC4D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_EEBCC4573EA45A475EF0E9233187FC4D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_56508FF5FB9C40183CDEE92331872762" xlink:to="loc_us-gaap_EquityComponentDomain_EEBCC4573EA45A475EF0E9233187FC4D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_08AB782D6569ABFE329EE92331886A48" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_EEBCC4573EA45A475EF0E9233187FC4D" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_08AB782D6569ABFE329EE92331886A48" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedTranslationAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_480B92C376E9AA02CF38E9233188831F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_EEBCC4573EA45A475EF0E9233187FC4D" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_480B92C376E9AA02CF38E9233188831F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_549A0EFFA8BCED9E4AA9E923318893F3" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_EEBCC4573EA45A475EF0E9233187FC4D" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_549A0EFFA8BCED9E4AA9E923318893F3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_3DA6BBCB27F55BA3DE2FE92331897293" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_9283D744D73E3FE2319CE92331884456" xlink:to="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_3DA6BBCB27F55BA3DE2FE92331897293" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_D978B2B41C7A5E7663DDE923318938BB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_3DA6BBCB27F55BA3DE2FE92331897293" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_D978B2B41C7A5E7663DDE923318938BB" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect" xlink:label="loc_uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect_6CD6CD911BF9E4FC6C5EE92331897644" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_3DA6BBCB27F55BA3DE2FE92331897293" xlink:to="loc_uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect_6CD6CD911BF9E4FC6C5EE92331897644" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_4B2A71ED320D521D214FE92331897E45" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_3DA6BBCB27F55BA3DE2FE92331897293" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_4B2A71ED320D521D214FE92331897E45" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_E0D26C23DDBFB2CBABB5E9233189E1AB" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_3DA6BBCB27F55BA3DE2FE92331897293" xlink:to="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax_E0D26C23DDBFB2CBABB5E9233189E1AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_5AEF13AEF309972A5C84E923318A9720" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_3DA6BBCB27F55BA3DE2FE92331897293" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_5AEF13AEF309972A5C84E923318A9720" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeNoncontrollingInterestsDetail" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/AccumulatedOtherComprehensiveIncomeTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/BasisOfPresentation" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/CommitmentsAndContingencies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/CommitmentsAndContingenciesAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingenciesLineItems" xlink:label="loc_us-gaap_LossContingenciesLineItems_27512182450D5D47AB18E64730007BBF" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingenciesTable" xlink:label="loc_us-gaap_LossContingenciesTable_D6184BE1AEAD5A46ABF1739BEC44D0D8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_27512182450D5D47AB18E64730007BBF" xlink:to="loc_us-gaap_LossContingenciesTable_D6184BE1AEAD5A46ABF1739BEC44D0D8" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_51A7644366CA526C932041DB829E182B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_D6184BE1AEAD5A46ABF1739BEC44D0D8" xlink:to="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_51A7644366CA526C932041DB829E182B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_414B9C5A957A6C4D413E8AE2F2D679A4_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_51A7644366CA526C932041DB829E182B" xlink:to="loc_us-gaap_LossContingencyNatureDomain_414B9C5A957A6C4D413E8AE2F2D679A4_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_C92441C3701854AF84D7B4603B296092" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_51A7644366CA526C932041DB829E182B" xlink:to="loc_us-gaap_LossContingencyNatureDomain_C92441C3701854AF84D7B4603B296092" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_MinistryOfJusticeOfBelgiumMember" xlink:label="loc_uis_MinistryOfJusticeOfBelgiumMember_5BB6389AC1E85040977DF3D47310093C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_C92441C3701854AF84D7B4603B296092" xlink:to="loc_uis_MinistryOfJusticeOfBelgiumMember_5BB6389AC1E85040977DF3D47310093C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InsuranceClaimsMember" xlink:label="loc_us-gaap_InsuranceClaimsMember_9EE1FD181C2D5EF09338E022D8FE2CBD" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_C92441C3701854AF84D7B4603B296092" xlink:to="loc_us-gaap_InsuranceClaimsMember_9EE1FD181C2D5EF09338E022D8FE2CBD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LossContingencyDamagesSoughtValue" xlink:label="loc_us-gaap_LossContingencyDamagesSoughtValue_73B8F5D252335793A8CE066A3EFE06FA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_27512182450D5D47AB18E64730007BBF" xlink:to="loc_us-gaap_LossContingencyDamagesSoughtValue_73B8F5D252335793A8CE066A3EFE06FA" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ContractTerminationCounterclaimsGovernmentsOtherThanUSFederalGovernment" xlink:label="loc_uis_ContractTerminationCounterclaimsGovernmentsOtherThanUSFederalGovernment_60080910201852969E93BEE72DB77C09" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_27512182450D5D47AB18E64730007BBF" xlink:to="loc_uis_ContractTerminationCounterclaimsGovernmentsOtherThanUSFederalGovernment_60080910201852969E93BEE72DB77C09" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_UnreservedTaxRelatedMattersInclusiveOfInterest" xlink:label="loc_uis_UnreservedTaxRelatedMattersInclusiveOfInterest_094164EB82DE512B99EC104F0E2526C6" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingenciesLineItems_27512182450D5D47AB18E64730007BBF" xlink:to="loc_uis_UnreservedTaxRelatedMattersInclusiveOfInterest_094164EB82DE512B99EC104F0E2526C6" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/ConsolidatedBalanceSheetsUnaudited" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/ConsolidatedBalanceSheetsUnauditedParenthetical" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/ConsolidatedStatementsOfCashFlowsUnaudited" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/ConsolidatedStatementsOfComprehensiveIncomeUnaudited" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/ConsolidatedStatementsOfComprehensiveIncomeUnauditedParenthetical" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/ConsolidatedStatementsOfDeficitUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_CAB2CAED9794DE6BD41FC55B9494747D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_37262A2C46839B31FC55C55B94903C0B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_CAB2CAED9794DE6BD41FC55B9494747D" xlink:to="loc_us-gaap_StatementTable_37262A2C46839B31FC55C55B94903C0B" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_9D375336D054259E1947C55B9491624F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_37262A2C46839B31FC55C55B94903C0B" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_9D375336D054259E1947C55B9491624F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_59F35915BFCF1E4F55DAC55B94915DEE_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_9D375336D054259E1947C55B9491624F" xlink:to="loc_us-gaap_EquityComponentDomain_59F35915BFCF1E4F55DAC55B94915DEE_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_59F35915BFCF1E4F55DAC55B94915DEE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_9D375336D054259E1947C55B9491624F" xlink:to="loc_us-gaap_EquityComponentDomain_59F35915BFCF1E4F55DAC55B94915DEE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ParentMember" xlink:label="loc_us-gaap_ParentMember_A11136351B0747487F28C55B9491AA93" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_59F35915BFCF1E4F55DAC55B94915DEE" xlink:to="loc_us-gaap_ParentMember_A11136351B0747487F28C55B9491AA93" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_86922BF9B7940E7C926FC55B94922F49" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_A11136351B0747487F28C55B9491AA93" xlink:to="loc_us-gaap_CommonStockMember_86922BF9B7940E7C926FC55B94922F49" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_729F3BB2BCB5EA4DDC64C55B9492359E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_A11136351B0747487F28C55B9491AA93" xlink:to="loc_us-gaap_RetainedEarningsMember_729F3BB2BCB5EA4DDC64C55B9492359E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="loc_us-gaap_TreasuryStockMember_E07F4E869405D7A701DBC55B9492A373" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_A11136351B0747487F28C55B9491AA93" xlink:to="loc_us-gaap_TreasuryStockMember_E07F4E869405D7A701DBC55B9492A373" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_3F9362D3471637C78EEEC55B94926C3B" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_A11136351B0747487F28C55B9491AA93" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_3F9362D3471637C78EEEC55B94926C3B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_1C3E9B54EF37FD0CE550C55B9493293B" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ParentMember_A11136351B0747487F28C55B9491AA93" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_1C3E9B54EF37FD0CE550C55B9493293B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaap_NoncontrollingInterestMember_EE51FD16B6780F409805C55B9493C399" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_59F35915BFCF1E4F55DAC55B94915DEE" xlink:to="loc_us-gaap_NoncontrollingInterestMember_EE51FD16B6780F409805C55B9493C399" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_9765CFEA93E164A0B40CC55B9493DC06" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_37262A2C46839B31FC55C55B94903C0B" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_9765CFEA93E164A0B40CC55B9493DC06" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_BD6825BC0F91998D50E5C55B949391E8_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_9765CFEA93E164A0B40CC55B9493DC06" xlink:to="loc_us-gaap_TypeOfAdoptionMember_BD6825BC0F91998D50E5C55B949391E8_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_BD6825BC0F91998D50E5C55B949391E8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_9765CFEA93E164A0B40CC55B9493DC06" xlink:to="loc_us-gaap_TypeOfAdoptionMember_BD6825BC0F91998D50E5C55B949391E8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member_5BFA4E77E9548B7D140BC55B94936A63" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_BD6825BC0F91998D50E5C55B949391E8" xlink:to="loc_us-gaap_AccountingStandardsUpdate201409Member_5BFA4E77E9548B7D140BC55B94936A63" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AccountingStandardsUpdate201616Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201616Member_48D2B775B467DB8C952EC55B94943E70" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_BD6825BC0F91998D50E5C55B949391E8" xlink:to="loc_us-gaap_AccountingStandardsUpdate201616Member_48D2B775B467DB8C952EC55B94943E70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_CAB2CAED9794DE6BD41FC55B9494747D" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_C6606CC77292BE637DE8C55B9494D648" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_C6606CC77292BE637DE8C55B9494D648" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption" xlink:label="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_A23D009E84B116155123C55B9495E685" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:to="loc_us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption_A23D009E84B116155123C55B9495E685" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect" xlink:label="loc_uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect_955E49144AF214427A97C55B9495CC51" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:to="loc_uis_TaxCutsandJobsActReclassificationfromAOCItoRetainedEarningsTaxEffect_955E49144AF214427A97C55B9495CC51" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_18AB776E849C1168ACE2C55B949570C8" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:to="loc_us-gaap_ProfitLoss_18AB776E849C1168ACE2C55B949570C8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_59D242E2A4294ED37E3CC55B94959B94" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:to="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_59D242E2A4294ED37E3CC55B94959B94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_AA830C01F3994A248C75C55B94953DFE" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_AA830C01F3994A248C75C55B94953DFE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_C4E319C7C261C2637678C55B9496A29C" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_5D63CDFB9066C7723D97C55B9494D2DC" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_C4E319C7C261C2637678C55B9496A29C" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/ConsolidatedStatementsOfIncomeUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_66DDAB53E8B6AFB76A137C8B39C1B9E1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_StatementTable_66DDAB53E8B6AFB76A137C8B39C1B9E1" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_75131395C54EF6E47C4B7C8B39C1819D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_66DDAB53E8B6AFB76A137C8B39C1B9E1" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_75131395C54EF6E47C4B7C8B39C1819D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_AF20BA128CD0E131D4F07C8B39C100A9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_75131395C54EF6E47C4B7C8B39C1819D" xlink:to="loc_us-gaap_SegmentDomain_AF20BA128CD0E131D4F07C8B39C100A9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_AF20BA128CD0E131D4F07C8B39C100A9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_75131395C54EF6E47C4B7C8B39C1819D" xlink:to="loc_us-gaap_SegmentDomain_AF20BA128CD0E131D4F07C8B39C100A9" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ServicesMember" xlink:label="loc_uis_ServicesMember_353C6137E537020012917C8B39C2D2AA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_AF20BA128CD0E131D4F07C8B39C100A9" xlink:to="loc_uis_ServicesMember_353C6137E537020012917C8B39C2D2AA" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_66A9FAD48CD952CAE5827C8B39C2305E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_AF20BA128CD0E131D4F07C8B39C100A9" xlink:to="loc_uis_TechnologyMember_66A9FAD48CD952CAE5827C8B39C2305E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenuesAbstract" xlink:label="loc_us-gaap_RevenuesAbstract_AFCDA130A49B2A789A4C7C8B39C2A32C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_RevenuesAbstract_AFCDA130A49B2A789A4C7C8B39C2A32C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_F328DE0697AD9EFB68957C8B39C3A30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesAbstract_AFCDA130A49B2A789A4C7C8B39C2A32C" xlink:to="loc_us-gaap_Revenues_F328DE0697AD9EFB68957C8B39C3A30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostsAndExpensesAbstract" xlink:label="loc_us-gaap_CostsAndExpensesAbstract_9291CFD159F101A033EF7C8B39C359D0" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_CostsAndExpensesAbstract_9291CFD159F101A033EF7C8B39C359D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostOfRevenueAbstract" xlink:label="loc_us-gaap_CostOfRevenueAbstract_5D332C43756F5FDE282F7C8B39C37329" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_9291CFD159F101A033EF7C8B39C359D0" xlink:to="loc_us-gaap_CostOfRevenueAbstract_5D332C43756F5FDE282F7C8B39C37329" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaap_CostOfRevenue_A2628AFEF7182079E20F7C8B39C427F8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostOfRevenueAbstract_5D332C43756F5FDE282F7C8B39C37329" xlink:to="loc_us-gaap_CostOfRevenue_A2628AFEF7182079E20F7C8B39C427F8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_CE997E99381A611DCAA57C8B39C48742" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_9291CFD159F101A033EF7C8B39C359D0" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_CE997E99381A611DCAA57C8B39C48742" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_F1E4F154657C1609B4497C8B39C43E6A" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_9291CFD159F101A033EF7C8B39C359D0" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_F1E4F154657C1609B4497C8B39C43E6A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostsAndExpenses" xlink:label="loc_us-gaap_CostsAndExpenses_ADCBDDE242C62F729E2E7C8B39C4FA77" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CostsAndExpensesAbstract_9291CFD159F101A033EF7C8B39C359D0" xlink:to="loc_us-gaap_CostsAndExpenses_ADCBDDE242C62F729E2E7C8B39C4FA77" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_844761A4F9E64A05C3407C8B39C4F29D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_OperatingIncomeLoss_844761A4F9E64A05C3407C8B39C4F29D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_9B1AD467E9CAD696C8887C8B39C500E6" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_InterestExpense_9B1AD467E9CAD696C8887C8B39C500E6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_0152F1A5D05F829B07927C8B39C5F265" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_0152F1A5D05F829B07927C8B39C5F265" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_D3C6FD62946C5484A8807C8B39C54860" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_D3C6FD62946C5484A8807C8B39C54860" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_5D5C317362CFD0B4369C7C8B39C5F6CA" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_5D5C317362CFD0B4369C7C8B39C5F6CA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_59E856CC804C004860357C8B39C5B94E" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_ProfitLoss_59E856CC804C004860357C8B39C5B94E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity_A900372BE4AB306D4ECE7C8B39C5B6F0" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsAttributableToNoncontrollingEntity_A900372BE4AB306D4ECE7C8B39C5B6F0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_8E32E6C5EFD8132F5C427C8B39C6EE79" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_NetIncomeLoss_8E32E6C5EFD8132F5C427C8B39C6EE79" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_78D43DA4B92D005B1A647C8B39C64E84" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_9F13B82F375EEE1D89747C8B39C2EA45" xlink:to="loc_us-gaap_EarningsPerShareAbstract_78D43DA4B92D005B1A647C8B39C64E84" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_D80EBD3D3EE1F4C2C9157C8B39C6DC33" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_78D43DA4B92D005B1A647C8B39C64E84" xlink:to="loc_us-gaap_EarningsPerShareBasic_D80EBD3D3EE1F4C2C9157C8B39C6DC33" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_C5A401C801E4BD0A9DC97C8B39C64DF4" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareAbstract_78D43DA4B92D005B1A647C8B39C64E84" xlink:to="loc_us-gaap_EarningsPerShareDiluted_C5A401C801E4BD0A9DC97C8B39C64DF4" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/CostReductionActions" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/CostReductionActionsAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCostAndReserveLineItems" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_B946ACB71FA14C2E11C584E0ACBD5ECC" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_4ECC0217288E311CF92784E0ACB8C199" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_B946ACB71FA14C2E11C584E0ACBD5ECC" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_4ECC0217288E311CF92784E0ACB8C199" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srt_StatementGeographicalAxis_1A997EAE5B490DC9D86E84E0ACB8368C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_4ECC0217288E311CF92784E0ACB8C199" xlink:to="loc_srt_StatementGeographicalAxis_1A997EAE5B490DC9D86E84E0ACB8368C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_E45CC4C255AB1B4BE1D184E0ACB91DA2_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_1A997EAE5B490DC9D86E84E0ACB8368C" xlink:to="loc_srt_SegmentGeographicalDomain_E45CC4C255AB1B4BE1D184E0ACB91DA2_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_E45CC4C255AB1B4BE1D184E0ACB91DA2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_1A997EAE5B490DC9D86E84E0ACB8368C" xlink:to="loc_srt_SegmentGeographicalDomain_E45CC4C255AB1B4BE1D184E0ACB91DA2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_16E6CD09E396E32AD6B984E0ACB9AFF6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_E45CC4C255AB1B4BE1D184E0ACB91DA2" xlink:to="loc_country_US_16E6CD09E396E32AD6B984E0ACB9AFF6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonUsMember" xlink:label="loc_us-gaap_NonUsMember_545B38A78DD99401DB6884E0ACB90B89" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_E45CC4C255AB1B4BE1D184E0ACB91DA2" xlink:to="loc_us-gaap_NonUsMember_545B38A78DD99401DB6884E0ACB90B89" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCostAndReserveAxis" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_1B13588E079FA944AC0384E0ACB9055E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_4ECC0217288E311CF92784E0ACB8C199" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_1B13588E079FA944AC0384E0ACB9055E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_1B13588E079FA944AC0384E0ACB9055E" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_1B13588E079FA944AC0384E0ACB9055E" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_EmployeeSeveranceandIdleLeasedFacilitiesMember" xlink:label="loc_uis_EmployeeSeveranceandIdleLeasedFacilitiesMember_6F97BB3C0029DF78556F84E0ACBAB7C1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_uis_EmployeeSeveranceandIdleLeasedFacilitiesMember_6F97BB3C0029DF78556F84E0ACBAB7C1" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_RestructuringReserveAccrualAdjustmentMember" xlink:label="loc_uis_RestructuringReserveAccrualAdjustmentMember_CAD36EFC5395B0DCDC2584E0ACBA9A71" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_uis_RestructuringReserveAccrualAdjustmentMember_CAD36EFC5395B0DCDC2584E0ACBA9A71" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_EmployeeSeveranceAdditionalBenefitsProvidedMember" xlink:label="loc_uis_EmployeeSeveranceAdditionalBenefitsProvidedMember_DC58930351AA98AA481D84E0ACBA941A" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_uis_EmployeeSeveranceAdditionalBenefitsProvidedMember_DC58930351AA98AA481D84E0ACBA941A" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_IdleLeasedFacilitiesMember" xlink:label="loc_uis_IdleLeasedFacilitiesMember_8DFFE409E339FCF8C7CE84E0ACBAFF99" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_uis_IdleLeasedFacilitiesMember_8DFFE409E339FCF8C7CE84E0ACBAFF99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ContractTerminationMember" xlink:label="loc_us-gaap_ContractTerminationMember_8938DC2C44DE97031D2C84E0ACBB31AD" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_us-gaap_ContractTerminationMember_8938DC2C44DE97031D2C84E0ACBB31AD" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ProfessionalFeesandOtherMember" xlink:label="loc_uis_ProfessionalFeesandOtherMember_92CDA63EBF26556B991B84E0ACBB2FF9" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_uis_ProfessionalFeesandOtherMember_92CDA63EBF26556B991B84E0ACBB2FF9" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_NetAssetSalesandWriteOffsMember" xlink:label="loc_uis_NetAssetSalesandWriteOffsMember_4C5450561810E105C45284E0ACBB01E4" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_uis_NetAssetSalesandWriteOffsMember_4C5450561810E105C45284E0ACBB01E4" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ForeignCurrencyTranslationAdjustmentMember" xlink:label="loc_uis_ForeignCurrencyTranslationAdjustmentMember_E179E5A2D4E52CD82CAD84E0ACBB354F" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_7D1FF2D7EC2A802771F784E0ACB9D6C7" xlink:to="loc_uis_ForeignCurrencyTranslationAdjustmentMember_E179E5A2D4E52CD82CAD84E0ACBB354F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_598DE6541AABE69A4D3084E0ACBB5008" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_4ECC0217288E311CF92784E0ACB8C199" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_598DE6541AABE69A4D3084E0ACBB5008" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_598DE6541AABE69A4D3084E0ACBB5008" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_598DE6541AABE69A4D3084E0ACBB5008" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="loc_us-gaap_CostOfSalesMember_2823BE12002F4F27256684E0ACBCDA11" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA" xlink:to="loc_us-gaap_CostOfSalesMember_2823BE12002F4F27256684E0ACBCDA11" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpensesMember" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpensesMember_AE671D3AC8AE3D25227584E0ACBC12B9" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpensesMember_AE671D3AC8AE3D25227584E0ACBC12B9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember_B69D2A69021A228A438B84E0ACBCE889" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpenseMember_B69D2A69021A228A438B84E0ACBCE889" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpenseMember" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_A5282B5275C33D3B0CAF84E0ACBCDE49" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_F91DE9C89644361F913084E0ACBB53CA" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_A5282B5275C33D3B0CAF84E0ACBCDE49" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_61FF0A6C0BBF133259AF84E0ACBD70FC" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_4ECC0217288E311CF92784E0ACB8C199" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_61FF0A6C0BBF133259AF84E0ACBD70FC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_3BD9B4EA43BC8662C22F84E0ACBDC54B_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_61FF0A6C0BBF133259AF84E0ACBD70FC" xlink:to="loc_us-gaap_SegmentDomain_3BD9B4EA43BC8662C22F84E0ACBDC54B_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_3BD9B4EA43BC8662C22F84E0ACBDC54B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_61FF0A6C0BBF133259AF84E0ACBD70FC" xlink:to="loc_us-gaap_SegmentDomain_3BD9B4EA43BC8662C22F84E0ACBDC54B" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ServicesMember" xlink:label="loc_uis_ServicesMember_F2E29ADAB9B2ED576C7284E0ACBDD7A9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_3BD9B4EA43BC8662C22F84E0ACBDC54B" xlink:to="loc_uis_ServicesMember_F2E29ADAB9B2ED576C7284E0ACBDD7A9" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_2CFB79ECFD036C61A05184E0ACBD313E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_3BD9B4EA43BC8662C22F84E0ACBDC54B" xlink:to="loc_uis_TechnologyMember_2CFB79ECFD036C61A05184E0ACBD313E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_5C98D20A8526CF62A2C784E0ACBED09E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_B946ACB71FA14C2E11C584E0ACBD5ECC" xlink:to="loc_us-gaap_RestructuringCharges_5C98D20A8526CF62A2C784E0ACBED09E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserveAccrualAdjustment1" xlink:label="loc_us-gaap_RestructuringReserveAccrualAdjustment1_892D5B4B79F17BB6683F84E0ACBE8C70" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_B946ACB71FA14C2E11C584E0ACBD5ECC" xlink:to="loc_us-gaap_RestructuringReserveAccrualAdjustment1_892D5B4B79F17BB6683F84E0ACBE8C70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeveranceCosts1" xlink:label="loc_us-gaap_SeveranceCosts1_5F370AAA2B56A2A36D6784E0ACBEC99A" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_B946ACB71FA14C2E11C584E0ACBD5ECC" xlink:to="loc_us-gaap_SeveranceCosts1_5F370AAA2B56A2A36D6784E0ACBEC99A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringAndRelatedCostExpectedNumberOfPositionsEliminated" xlink:label="loc_us-gaap_RestructuringAndRelatedCostExpectedNumberOfPositionsEliminated_622BDDB9DB6D1B462F3E84E0ACBE14DE" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_B946ACB71FA14C2E11C584E0ACBD5ECC" xlink:to="loc_us-gaap_RestructuringAndRelatedCostExpectedNumberOfPositionsEliminated_622BDDB9DB6D1B462F3E84E0ACBE14DE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherRestructuringCosts" xlink:label="loc_us-gaap_OtherRestructuringCosts_A458C58C6A0CED526D8484E0ACBEF658" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_B946ACB71FA14C2E11C584E0ACBD5ECC" xlink:to="loc_us-gaap_OtherRestructuringCosts_A458C58C6A0CED526D8484E0ACBEF658" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/CostReductionActionsIndividualComponentsOfWorkForceReductionAndIdleLeaseCostDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCostAndReserveLineItems" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_1728E316FD08590EA1788F088960D7EA" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_CE39B0647E2E5190975FBC04BD87C2C7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_1728E316FD08590EA1788F088960D7EA" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_CE39B0647E2E5190975FBC04BD87C2C7" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCostAndReserveAxis" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_A044D610C39B5FD2BE5BE5D6ECC727A7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_CE39B0647E2E5190975FBC04BD87C2C7" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_A044D610C39B5FD2BE5BE5D6ECC727A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_FF18A20820390A8A2D2385D81E7A32B1_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_A044D610C39B5FD2BE5BE5D6ECC727A7" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_FF18A20820390A8A2D2385D81E7A32B1_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_EC3550B4A20950EB8BCD58B7A58DC34B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_A044D610C39B5FD2BE5BE5D6ECC727A7" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_EC3550B4A20950EB8BCD58B7A58DC34B" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_EmployeeSeveranceandIdleLeasedFacilitiesMember" xlink:label="loc_uis_EmployeeSeveranceandIdleLeasedFacilitiesMember_337494318F0058B4ACB3EBD5C1819C78" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_EC3550B4A20950EB8BCD58B7A58DC34B" xlink:to="loc_uis_EmployeeSeveranceandIdleLeasedFacilitiesMember_337494318F0058B4ACB3EBD5C1819C78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeSeveranceMember" xlink:label="loc_us-gaap_EmployeeSeveranceMember_A72B3494D5805CA7A63DB1DEF295F5DF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EmployeeSeveranceandIdleLeasedFacilitiesMember_337494318F0058B4ACB3EBD5C1819C78" xlink:to="loc_us-gaap_EmployeeSeveranceMember_A72B3494D5805CA7A63DB1DEF295F5DF" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_IdleLeasedFacilitiesMember" xlink:label="loc_uis_IdleLeasedFacilitiesMember_7BAED8FBE5AA567BBDE22A7E5BEF2C56" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_EmployeeSeveranceandIdleLeasedFacilitiesMember_337494318F0058B4ACB3EBD5C1819C78" xlink:to="loc_uis_IdleLeasedFacilitiesMember_7BAED8FBE5AA567BBDE22A7E5BEF2C56" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srt_StatementGeographicalAxis_66C38DB7BFDF59578BBBD2CCA6A7EE8D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_CE39B0647E2E5190975FBC04BD87C2C7" xlink:to="loc_srt_StatementGeographicalAxis_66C38DB7BFDF59578BBBD2CCA6A7EE8D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_05E0675A3B4A0674731685D81E7BD8BA_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_66C38DB7BFDF59578BBBD2CCA6A7EE8D" xlink:to="loc_srt_SegmentGeographicalDomain_05E0675A3B4A0674731685D81E7BD8BA_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_BD33460717B55863BEE734AA2326A939" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_66C38DB7BFDF59578BBBD2CCA6A7EE8D" xlink:to="loc_srt_SegmentGeographicalDomain_BD33460717B55863BEE734AA2326A939" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_3D46F38FD937510593F862950D98F5CC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_BD33460717B55863BEE734AA2326A939" xlink:to="loc_country_US_3D46F38FD937510593F862950D98F5CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NonUsMember" xlink:label="loc_us-gaap_NonUsMember_F5F0F370914D51C1878EACD78C70723F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_BD33460717B55863BEE734AA2326A939" xlink:to="loc_us-gaap_NonUsMember_F5F0F370914D51C1878EACD78C70723F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementScenarioAxis" xlink:label="loc_us-gaap_StatementScenarioAxis_8A80552E3D1454AFAFCC2B804B8FD5A3" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_CE39B0647E2E5190975FBC04BD87C2C7" xlink:to="loc_us-gaap_StatementScenarioAxis_8A80552E3D1454AFAFCC2B804B8FD5A3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_C76AD5662EED5411DA3A85D81E7C56D8_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementScenarioAxis_8A80552E3D1454AFAFCC2B804B8FD5A3" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_C76AD5662EED5411DA3A85D81E7C56D8_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioUnspecifiedDomain" xlink:label="loc_us-gaap_ScenarioUnspecifiedDomain_D8FCC37689F3529D82A651D42397BDB9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementScenarioAxis_8A80552E3D1454AFAFCC2B804B8FD5A3" xlink:to="loc_us-gaap_ScenarioUnspecifiedDomain_D8FCC37689F3529D82A651D42397BDB9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScenarioForecastMember" xlink:label="loc_us-gaap_ScenarioForecastMember_27EACFD555B7583BACDEEEB7C41F6A62" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScenarioUnspecifiedDomain_D8FCC37689F3529D82A651D42397BDB9" xlink:to="loc_us-gaap_ScenarioForecastMember_27EACFD555B7583BACDEEEB7C41F6A62" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserveRollForward" xlink:label="loc_us-gaap_RestructuringReserveRollForward_4F6DA870DA255C6BAE8F300DA32F74D4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_1728E316FD08590EA1788F088960D7EA" xlink:to="loc_us-gaap_RestructuringReserveRollForward_4F6DA870DA255C6BAE8F300DA32F74D4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserve" xlink:label="loc_us-gaap_RestructuringReserve_7895868AD1805064A9DAB560AEB5612A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_4F6DA870DA255C6BAE8F300DA32F74D4" xlink:to="loc_us-gaap_RestructuringReserve_7895868AD1805064A9DAB560AEB5612A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PaymentsForRestructuring" xlink:label="loc_us-gaap_PaymentsForRestructuring_CBD26C72646953798AAA8E760F331265" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_4F6DA870DA255C6BAE8F300DA32F74D4" xlink:to="loc_us-gaap_PaymentsForRestructuring_CBD26C72646953798AAA8E760F331265" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserveAccrualAdjustment1" xlink:label="loc_us-gaap_RestructuringReserveAccrualAdjustment1_D68A9A8528C95C568FBFF49CD9752552" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_4F6DA870DA255C6BAE8F300DA32F74D4" xlink:to="loc_us-gaap_RestructuringReserveAccrualAdjustment1_D68A9A8528C95C568FBFF49CD9752552" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringReserveTranslationAdjustment" xlink:label="loc_us-gaap_RestructuringReserveTranslationAdjustment_B7C08B676D8452CE92530CF325CDCDFE" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringReserveRollForward_4F6DA870DA255C6BAE8F300DA32F74D4" xlink:to="loc_us-gaap_RestructuringReserveTranslationAdjustment_B7C08B676D8452CE92530CF325CDCDFE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1" xlink:label="loc_us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1_F1A524088C2A5F3F9FFF342DB898E455" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_1728E316FD08590EA1788F088960D7EA" xlink:to="loc_us-gaap_RestructuringAndRelatedCostExpectedCostRemaining1_F1A524088C2A5F3F9FFF342DB898E455" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/CostReductionActionsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/Debt" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/DebtAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_6B04120A4D9EE11D00EBC55B934861DF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentTable_6B04120A4D9EE11D00EBC55B934861DF" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_0215C97802E36B5339D7C55B93481608" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_6B04120A4D9EE11D00EBC55B934861DF" xlink:to="loc_us-gaap_DebtInstrumentAxis_0215C97802E36B5339D7C55B93481608" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_840B24EB7C4E52386300C55B93499D20_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_0215C97802E36B5339D7C55B93481608" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_840B24EB7C4E52386300C55B93499D20_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_840B24EB7C4E52386300C55B93499D20" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_0215C97802E36B5339D7C55B93481608" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_840B24EB7C4E52386300C55B93499D20" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_SeniorSecuredNotesDue2022Member" xlink:label="loc_uis_SeniorSecuredNotesDue2022Member_1AD4FED65EF282D3DB79C55B9349B621" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_840B24EB7C4E52386300C55B93499D20" xlink:to="loc_uis_SeniorSecuredNotesDue2022Member_1AD4FED65EF282D3DB79C55B9349B621" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ConvertibleSeniorNotesDue2021Member" xlink:label="loc_uis_ConvertibleSeniorNotesDue2021Member_1E2C7ABE82EDD8F5E0B0C55B934952DB" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_840B24EB7C4E52386300C55B93499D20" xlink:to="loc_uis_ConvertibleSeniorNotesDue2021Member_1E2C7ABE82EDD8F5E0B0C55B934952DB" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_CreditAgreementMember" xlink:label="loc_uis_CreditAgreementMember_B7D2668CCCDA017BE79BC55B934953E7" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_840B24EB7C4E52386300C55B93499D20" xlink:to="loc_uis_CreditAgreementMember_B7D2668CCCDA017BE79BC55B934953E7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_BF3BDA1E4714338A59FAC55B934AF09D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_6B04120A4D9EE11D00EBC55B934861DF" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_BF3BDA1E4714338A59FAC55B934AF09D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_28132DCA4F4AFE8F6271C55B934AE577_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_BF3BDA1E4714338A59FAC55B934AF09D" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_28132DCA4F4AFE8F6271C55B934AE577_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_28132DCA4F4AFE8F6271C55B934AE577" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_BF3BDA1E4714338A59FAC55B934AF09D" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_28132DCA4F4AFE8F6271C55B934AE577" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_CABF5BC5498F2937FED0C55B934AF8EA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_28132DCA4F4AFE8F6271C55B934AE577" xlink:to="loc_us-gaap_SeniorNotesMember_CABF5BC5498F2937FED0C55B934AF8EA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaap_LineOfCreditMember_FA01C5E85F2E784EDE2DC55B934BB58F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_28132DCA4F4AFE8F6271C55B934AE577" xlink:to="loc_us-gaap_LineOfCreditMember_FA01C5E85F2E784EDE2DC55B934BB58F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_BF55BDC9FB667DCD8803C55B934BEF03" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_6B04120A4D9EE11D00EBC55B934861DF" xlink:to="loc_us-gaap_CreditFacilityAxis_BF55BDC9FB667DCD8803C55B934BEF03" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_7482F25FFC70B1902E05C55B934B698A_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_BF55BDC9FB667DCD8803C55B934BEF03" xlink:to="loc_us-gaap_CreditFacilityDomain_7482F25FFC70B1902E05C55B934B698A_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_7482F25FFC70B1902E05C55B934B698A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_BF55BDC9FB667DCD8803C55B934BEF03" xlink:to="loc_us-gaap_CreditFacilityDomain_7482F25FFC70B1902E05C55B934B698A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_101F0625C538AA78B9EAC55B934BAEA6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_7482F25FFC70B1902E05C55B934B698A" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_101F0625C538AA78B9EAC55B934BAEA6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LetterOfCreditMember" xlink:label="loc_us-gaap_LetterOfCreditMember_6CAF77D4830EB2DB9BE0C55B934CFF99" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_7482F25FFC70B1902E05C55B934B698A" xlink:to="loc_us-gaap_LetterOfCreditMember_6CAF77D4830EB2DB9BE0C55B934CFF99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_06D6FABC2315BAB01875C55B934DA523" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_06D6FABC2315BAB01875C55B934DA523" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_46FF2154A4A047480212C55B934DD19B" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_46FF2154A4A047480212C55B934DD19B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed_409E711C81BD1DE7A5DAC55B934DE261" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed_409E711C81BD1DE7A5DAC55B934DE261" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentRedemptionPercentageofNotes" xlink:label="loc_uis_DebtInstrumentRedemptionPercentageofNotes_75FDBA55C68ABAEEDB9CC55B934EB1E6" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentRedemptionPercentageofNotes_75FDBA55C68ABAEEDB9CC55B934EB1E6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentRedemptionPricePercentage" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_F26ACEE3E28F5AC7AC46C55B934E6E90" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPricePercentage_F26ACEE3E28F5AC7AC46C55B934E6E90" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantRequiredCollateralCoverageRatioNotMetRedemptionPricePercentage" xlink:label="loc_uis_DebtInstrumentCovenantRequiredCollateralCoverageRatioNotMetRedemptionPricePercentage_CB70A84D17D2BF3D5BE1C55B934EB743" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantRequiredCollateralCoverageRatioNotMetRedemptionPricePercentage_CB70A84D17D2BF3D5BE1C55B934EB743" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantCollateralCoverageRatioMinimum" xlink:label="loc_uis_DebtInstrumentCovenantCollateralCoverageRatioMinimum_2BE04D59F5C3C6D445A7C55B934EEAE2" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantCollateralCoverageRatioMinimum_2BE04D59F5C3C6D445A7C55B934EEAE2" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantCollateralCoverageRatioCalculationAmountAddedtoCashandCashEquivalents" xlink:label="loc_uis_DebtInstrumentCovenantCollateralCoverageRatioCalculationAmountAddedtoCashandCashEquivalents_0A2F6B9A0318F26F0CF2C55B934EAD32" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantCollateralCoverageRatioCalculationAmountAddedtoCashandCashEquivalents_0A2F6B9A0318F26F0CF2C55B934EAD32" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantCollateralCoverageRatioCalculationAverageGrantorEBITDAMultiplierforSevenMostRecentFiscalQuarters" xlink:label="loc_uis_DebtInstrumentCovenantCollateralCoverageRatioCalculationAverageGrantorEBITDAMultiplierforSevenMostRecentFiscalQuarters_ED7605E8AF1D8C20AA24C55B934E95BC" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantCollateralCoverageRatioCalculationAverageGrantorEBITDAMultiplierforSevenMostRecentFiscalQuarters_ED7605E8AF1D8C20AA24C55B934E95BC" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantRequiredCollateralCoverageRatioNotMetRedemptionPeriod" xlink:label="loc_uis_DebtInstrumentCovenantRequiredCollateralCoverageRatioNotMetRedemptionPeriod_0FD670E9CE82F7C6ACFDC55B934F6E1B" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantRequiredCollateralCoverageRatioNotMetRedemptionPeriod_0FD670E9CE82F7C6ACFDC55B934F6E1B" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantChangeinControlRedemptionPricePercentage" xlink:label="loc_uis_DebtInstrumentCovenantChangeinControlRedemptionPricePercentage_938D62C0D5E08C8B3C32C55B934F2D82" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantChangeinControlRedemptionPricePercentage_938D62C0D5E08C8B3C32C55B934F2D82" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_1969EC6D4F23B663E9EDC55B934FD23B" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_1969EC6D4F23B663E9EDC55B934FD23B" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentConvertibleConversionRate" xlink:label="loc_uis_DebtInstrumentConvertibleConversionRate_4582B9DD0F7B700192A4C55B934FC7B4" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentConvertibleConversionRate_4582B9DD0F7B700192A4C55B934FC7B4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments" xlink:label="loc_us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments_774BE84A261FC95E96B5C55B934F2745" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentConvertibleNumberOfEquityInstruments_774BE84A261FC95E96B5C55B934F2745" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_A5BE995108D4264064FFC55B934FC02D" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_A5BE995108D4264064FFC55B934FC02D" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_PaymentsForCappedCallTransactions" xlink:label="loc_uis_PaymentsForCappedCallTransactions_21280F1872B73BEB24B3C55B934F1F91" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_PaymentsForCappedCallTransactions_21280F1872B73BEB24B3C55B934F1F91" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentConversionPremium" xlink:label="loc_uis_DebtInstrumentConversionPremium_047E83F9CF461C59B8DAC55B93507A31" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentConversionPremium_047E83F9CF461C59B8DAC55B93507A31" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_D47CC1C1B40592D392C7C55B9350E574" xlink:type="locator" />
    <link:definitionArc order="18" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_D47CC1C1B40592D392C7C55B9350E574" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_LineofCreditFacilityAccordionFeatureIncreaseLimit" xlink:label="loc_uis_LineofCreditFacilityAccordionFeatureIncreaseLimit_79D2B17DC8813FB59953C55B9350DEDC" xlink:type="locator" />
    <link:definitionArc order="19" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_LineofCreditFacilityAccordionFeatureIncreaseLimit_79D2B17DC8813FB59953C55B9350DEDC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_C1CBE402C769B6B422C9C55B9350C923" xlink:type="locator" />
    <link:definitionArc order="20" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_LineOfCredit_C1CBE402C769B6B422C9C55B9350C923" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LettersOfCreditOutstandingAmount" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_3828ED5B99F5BA3EE4E0C55B9350B5EC" xlink:type="locator" />
    <link:definitionArc order="21" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_LettersOfCreditOutstandingAmount_3828ED5B99F5BA3EE4E0C55B9350B5EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_D5595F76CA2B95BC9C74C55B9351A86A" xlink:type="locator" />
    <link:definitionArc order="22" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_D5595F76CA2B95BC9C74C55B9351A86A" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_LineofCreditFacilitySpringingMaturityDatePeriodPriortoMaturityDateofConvertibleDebt" xlink:label="loc_uis_LineofCreditFacilitySpringingMaturityDatePeriodPriortoMaturityDateofConvertibleDebt_84A31BD9845C388E32F7C55B9351DB45" xlink:type="locator" />
    <link:definitionArc order="23" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_LineofCreditFacilitySpringingMaturityDatePeriodPriortoMaturityDateofConvertibleDebt_84A31BD9845C388E32F7C55B9351DB45" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_LineofCreditFacilitySpringingMaturityDatePeriodPriortoMaturityDateofSecuredDebt" xlink:label="loc_uis_LineofCreditFacilitySpringingMaturityDatePeriodPriortoMaturityDateofSecuredDebt_FB23939DBC0ED6D6CF06C55B93517D35" xlink:type="locator" />
    <link:definitionArc order="24" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_LineofCreditFacilitySpringingMaturityDatePeriodPriortoMaturityDateofSecuredDebt_FB23939DBC0ED6D6CF06C55B93517D35" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantMinimumFixedChargeCoverageRatioAvailableBorrowingsThresholdPercentofLenderCommitments" xlink:label="loc_uis_DebtInstrumentCovenantMinimumFixedChargeCoverageRatioAvailableBorrowingsThresholdPercentofLenderCommitments_76EE41BA7CCE1F9F4FA2C55B93514831" xlink:type="locator" />
    <link:definitionArc order="25" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantMinimumFixedChargeCoverageRatioAvailableBorrowingsThresholdPercentofLenderCommitments_76EE41BA7CCE1F9F4FA2C55B93514831" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentCovenantMinimumFixedChargeCoverageRatioAvailableBorrowingsThreshold" xlink:label="loc_uis_DebtInstrumentCovenantMinimumFixedChargeCoverageRatioAvailableBorrowingsThreshold_5D04D9EC7687658ED67AC55B9351223F" xlink:type="locator" />
    <link:definitionArc order="26" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentCovenantMinimumFixedChargeCoverageRatioAvailableBorrowingsThreshold_5D04D9EC7687658ED67AC55B9351223F" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_DebtInstrumentDebtDefaultTriggeringEventThresholdAmount" xlink:label="loc_uis_DebtInstrumentDebtDefaultTriggeringEventThresholdAmount_717F0D02B68A456A9245C55B93526579" xlink:type="locator" />
    <link:definitionArc order="27" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_CA5F55AA5F63EFA737B8C55B934D15E1" xlink:to="loc_uis_DebtInstrumentDebtDefaultTriggeringEventThresholdAmount_717F0D02B68A456A9245C55B93526579" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/DebtScheduleOfComponentsOfLongTermDebtDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_14F6599827A050C9A9DC4304280CAB68" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_DebtInstrumentTable_14F6599827A050C9A9DC4304280CAB68" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_2947EF6F46625CF18BB154C146DFB1DF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_14F6599827A050C9A9DC4304280CAB68" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_2947EF6F46625CF18BB154C146DFB1DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_A80EE78DA521596D2EFD8AE2F33052F9_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_2947EF6F46625CF18BB154C146DFB1DF" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_A80EE78DA521596D2EFD8AE2F33052F9_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_F5D3AB62700D5E4A8B3EFA0EFAF94D37" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_2947EF6F46625CF18BB154C146DFB1DF" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_F5D3AB62700D5E4A8B3EFA0EFAF94D37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_584236E084755965883BF3012EAE0232" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_F5D3AB62700D5E4A8B3EFA0EFAF94D37" xlink:to="loc_us-gaap_SeniorNotesMember_584236E084755965883BF3012EAE0232" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalLeaseObligationsMember" xlink:label="loc_us-gaap_CapitalLeaseObligationsMember_34AB24F6ECA4506B88E469F284CDB53D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_F5D3AB62700D5E4A8B3EFA0EFAF94D37" xlink:to="loc_us-gaap_CapitalLeaseObligationsMember_34AB24F6ECA4506B88E469F284CDB53D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_5C094324047A5F348C83A1D5C8BD7D60" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_14F6599827A050C9A9DC4304280CAB68" xlink:to="loc_us-gaap_DebtInstrumentAxis_5C094324047A5F348C83A1D5C8BD7D60" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_43F990B2D2DA372CF8758AE2F331DBFB_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_5C094324047A5F348C83A1D5C8BD7D60" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_43F990B2D2DA372CF8758AE2F331DBFB_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_F31F56EB61635AF6BBD84BEEAEBCE383" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_5C094324047A5F348C83A1D5C8BD7D60" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_F31F56EB61635AF6BBD84BEEAEBCE383" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TenPointSevenFivePercentageSeniorSecuredNotesDueinAprilTwoThousandTwentyTwoMember" xlink:label="loc_uis_TenPointSevenFivePercentageSeniorSecuredNotesDueinAprilTwoThousandTwentyTwoMember_F96FE8544B675DBFBCD203BCF7B2983E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_F31F56EB61635AF6BBD84BEEAEBCE383" xlink:to="loc_uis_TenPointSevenFivePercentageSeniorSecuredNotesDueinAprilTwoThousandTwentyTwoMember_F96FE8544B675DBFBCD203BCF7B2983E" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ConvertibleSeniorNotesDue2021Member" xlink:label="loc_uis_ConvertibleSeniorNotesDue2021Member_FAE5E3F0231758BD8E6C5D1B80995B5E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_F31F56EB61635AF6BBD84BEEAEBCE383" xlink:to="loc_uis_ConvertibleSeniorNotesDue2021Member_FAE5E3F0231758BD8E6C5D1B80995B5E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_0AD818EB2E0C5D4893A96545CDF033AC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_0AD818EB2E0C5D4893A96545CDF033AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_C666DFB6F32F595CAD6E131B6FB15506" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_C666DFB6F32F595CAD6E131B6FB15506" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentUnamortizedDiscount" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscount_800D6246F78255838E219A3425EE2CF0" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscount_800D6246F78255838E219A3425EE2CF0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_8D9C9BE4B44E5A059070DA7B87E8E8FE" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_8D9C9BE4B44E5A059070DA7B87E8E8FE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalLeaseObligationsNoncurrent" xlink:label="loc_us-gaap_CapitalLeaseObligationsNoncurrent_8BD1EAFF8F025F2F9E992A590D7AF4F9" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_CapitalLeaseObligationsNoncurrent_8BD1EAFF8F025F2F9E992A590D7AF4F9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherLongTermDebt" xlink:label="loc_us-gaap_OtherLongTermDebt_CD298C9EB0D557F38CD9AB701D0DFB41" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_OtherLongTermDebt_CD298C9EB0D557F38CD9AB701D0DFB41" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_B575421E6F1850339FD9A83238CFC910" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_B575421E6F1850339FD9A83238CFC910" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_CDCA6C8FF0075AE2BCFEB1A68B9FD88E" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_CDCA6C8FF0075AE2BCFEB1A68B9FD88E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_F04BEB7AADA358FE969AF8CE372E63E4" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_58459DB45A0D5052A8C4CCA74C1BF171" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_F04BEB7AADA358FE969AF8CE372E63E4" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/DebtScheduleOfInterestExpenseDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_81DEE2C6B20E5E9787385D80FBA51474" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_4B7B6B38E26A5060BE260D46FFDF4DC4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_81DEE2C6B20E5E9787385D80FBA51474" xlink:to="loc_us-gaap_DebtInstrumentTable_4B7B6B38E26A5060BE260D46FFDF4DC4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_97A2B8087CE55A12AACDE2F7936273FA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_4B7B6B38E26A5060BE260D46FFDF4DC4" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_97A2B8087CE55A12AACDE2F7936273FA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_B93D0F02153D1620FEE293D475A2BC52_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_97A2B8087CE55A12AACDE2F7936273FA" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_B93D0F02153D1620FEE293D475A2BC52_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_E9D0CBEC95DA5AA7A960E667A5C385EC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_97A2B8087CE55A12AACDE2F7936273FA" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_E9D0CBEC95DA5AA7A960E667A5C385EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_6FC115D82FE552E5AEED8679A6E81E8B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_E9D0CBEC95DA5AA7A960E667A5C385EC" xlink:to="loc_us-gaap_SeniorNotesMember_6FC115D82FE552E5AEED8679A6E81E8B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_EF4B7BA7CC69527F91E76CE029B7AE04" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_4B7B6B38E26A5060BE260D46FFDF4DC4" xlink:to="loc_us-gaap_DebtInstrumentAxis_EF4B7BA7CC69527F91E76CE029B7AE04" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_42FBC2D3EBF11DEFEDEF93D475A34F57_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_EF4B7BA7CC69527F91E76CE029B7AE04" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_42FBC2D3EBF11DEFEDEF93D475A34F57_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_FCCD92BDAF7C5FC58FD2806090167C83" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_EF4B7BA7CC69527F91E76CE029B7AE04" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_FCCD92BDAF7C5FC58FD2806090167C83" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ConvertibleSeniorNotesDue2021Member" xlink:label="loc_uis_ConvertibleSeniorNotesDue2021Member_ED0C6B77FF7053BE9BFCCFA17071A5B6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_FCCD92BDAF7C5FC58FD2806090167C83" xlink:to="loc_uis_ConvertibleSeniorNotesDue2021Member_ED0C6B77FF7053BE9BFCCFA17071A5B6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpenseDebtExcludingAmortization" xlink:label="loc_us-gaap_InterestExpenseDebtExcludingAmortization_DE652A57DCB0506392B094BA93578FFC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_81DEE2C6B20E5E9787385D80FBA51474" xlink:to="loc_us-gaap_InterestExpenseDebtExcludingAmortization_DE652A57DCB0506392B094BA93578FFC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AmortizationOfDebtDiscountPremium" xlink:label="loc_us-gaap_AmortizationOfDebtDiscountPremium_6F57A8E5E75F514ABA0597896125B97A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_81DEE2C6B20E5E9787385D80FBA51474" xlink:to="loc_us-gaap_AmortizationOfDebtDiscountPremium_6F57A8E5E75F514ABA0597896125B97A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_4B25DB20331D5CEDB4332B092884CE28" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_81DEE2C6B20E5E9787385D80FBA51474" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_4B25DB20331D5CEDB4332B092884CE28" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpenseDebt" xlink:label="loc_us-gaap_InterestExpenseDebt_71231B7DFB9956FD993FAA66FCAA11DA" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_81DEE2C6B20E5E9787385D80FBA51474" xlink:to="loc_us-gaap_InterestExpenseDebt_71231B7DFB9956FD993FAA66FCAA11DA" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/DebtTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/DocumentAndEntityInformation" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/EarningsPerShare" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/EarningsPerShareComputationOfEarningsLossPerCommonShareAttributableToUnisysCorporationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_49433212DE5F5A608DEB9939996CCF71" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_6077F25CD6B95C55A5F1C0C73EEF6739" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_49433212DE5F5A608DEB9939996CCF71" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_6077F25CD6B95C55A5F1C0C73EEF6739" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_C41E012C67F7560496F4FAA0C9D51ADD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_6077F25CD6B95C55A5F1C0C73EEF6739" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_C41E012C67F7560496F4FAA0C9D51ADD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_A226CE138F1278D526118AE2F3BC05A5_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_C41E012C67F7560496F4FAA0C9D51ADD" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_A226CE138F1278D526118AE2F3BC05A5_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_05D9ECA315F5590BAD64B1077A3E456E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_C41E012C67F7560496F4FAA0C9D51ADD" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_05D9ECA315F5590BAD64B1077A3E456E" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_StockOptionsAndRestrictedStockUnitsMember" xlink:label="loc_uis_StockOptionsAndRestrictedStockUnitsMember_36855E8F78AA5CA381859A44A4D788C2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_05D9ECA315F5590BAD64B1077A3E456E" xlink:to="loc_uis_StockOptionsAndRestrictedStockUnitsMember_36855E8F78AA5CA381859A44A4D788C2" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ConvertibleSeniorNotesFivePointFivePercentDueTwentyTwentyOneMember" xlink:label="loc_uis_ConvertibleSeniorNotesFivePointFivePercentDueTwentyTwentyOneMember_A4D9ECA8296752ECBA3B72DAEB4D1DEC" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_05D9ECA315F5590BAD64B1077A3E456E" xlink:to="loc_uis_ConvertibleSeniorNotesFivePointFivePercentDueTwentyTwentyOneMember_A4D9ECA8296752ECBA3B72DAEB4D1DEC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_CE883173E0E55167B83ECCA6039B338F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_49433212DE5F5A608DEB9939996CCF71" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_CE883173E0E55167B83ECCA6039B338F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_CED329802D1853C4922F8C76312EF05A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_49433212DE5F5A608DEB9939996CCF71" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_CED329802D1853C4922F8C76312EF05A" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/EarningsPerShareTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurements" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="uis-20180930.xsd#uis_FairValueMeasurementsDisclosureLineItems" xlink:label="loc_uis_FairValueMeasurementsDisclosureLineItems_BB5467BA9E1E55D4B5A16B268F1D8A4C" xlink:type="locator" />
    <link:loc xlink:href="uis-20180930.xsd#uis_FairValueMeasurementsDisclosureTable" xlink:label="loc_uis_FairValueMeasurementsDisclosureTable_2C2058302250581390FA04DDA30F2D26" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_uis_FairValueMeasurementsDisclosureLineItems_BB5467BA9E1E55D4B5A16B268F1D8A4C" xlink:to="loc_uis_FairValueMeasurementsDisclosureTable_2C2058302250581390FA04DDA30F2D26" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_F1D55E63FB535D9B952DCF922FBE1E60" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_uis_FairValueMeasurementsDisclosureTable_2C2058302250581390FA04DDA30F2D26" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_F1D55E63FB535D9B952DCF922FBE1E60" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_D85CB919BB6C626C70CE147D03A83E89_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_F1D55E63FB535D9B952DCF922FBE1E60" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_D85CB919BB6C626C70CE147D03A83E89_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_FB1EB2F7D1795C9AB86546959E633BED" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_F1D55E63FB535D9B952DCF922FBE1E60" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_FB1EB2F7D1795C9AB86546959E633BED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignExchangeForwardMember" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_FD6402F60ED9581DBCBCC281C959C34A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_FB1EB2F7D1795C9AB86546959E633BED" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_FD6402F60ED9581DBCBCC281C959C34A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeTermOfContract" xlink:label="loc_us-gaap_DerivativeTermOfContract_C342C481FB945DD2B721761EDFB8F62B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_FairValueMeasurementsDisclosureLineItems_BB5467BA9E1E55D4B5A16B268F1D8A4C" xlink:to="loc_us-gaap_DerivativeTermOfContract_C342C481FB945DD2B721761EDFB8F62B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeAssetNotionalAmount" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_D7D16D411D6558FF8A0E6393C4F64434" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_uis_FairValueMeasurementsDisclosureLineItems_BB5467BA9E1E55D4B5A16B268F1D8A4C" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_D7D16D411D6558FF8A0E6393C4F64434" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsFairValueOfForeignExchangeForwardContractsByBalanceSheetLocationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems" xlink:label="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_6945831C3A9D5B4CB8C77527B4729406" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueByBalanceSheetGroupingTable" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTable_50057BD99DC15347804E6307244955A1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_6945831C3A9D5B4CB8C77527B4729406" xlink:to="loc_us-gaap_FairValueByBalanceSheetGroupingTable_50057BD99DC15347804E6307244955A1" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_105BFAA5374D5CBE8B4A96AC9BA2E54A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_50057BD99DC15347804E6307244955A1" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_105BFAA5374D5CBE8B4A96AC9BA2E54A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_8B0A07835242A538D2E3147D03A1DA0D_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_105BFAA5374D5CBE8B4A96AC9BA2E54A" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_8B0A07835242A538D2E3147D03A1DA0D_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_9A2DFCC8BC425CEF87A301EB25BCEEC6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_105BFAA5374D5CBE8B4A96AC9BA2E54A" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_9A2DFCC8BC425CEF87A301EB25BCEEC6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignExchangeForwardMember" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_C99BD085B8D35543B0E6648539E499D9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9A2DFCC8BC425CEF87A301EB25BCEEC6" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_C99BD085B8D35543B0E6648539E499D9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_A33A81BDB0D25B279FFBFD1D63FA9A24" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_50057BD99DC15347804E6307244955A1" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_A33A81BDB0D25B279FFBFD1D63FA9A24" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_84A5C6CDF8B739197693147D03A17B3B_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_A33A81BDB0D25B279FFBFD1D63FA9A24" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_84A5C6CDF8B739197693147D03A17B3B_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_A2F9125AE59259EF887DA08474CCAF64" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_A33A81BDB0D25B279FFBFD1D63FA9A24" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_A2F9125AE59259EF887DA08474CCAF64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember" xlink:label="loc_us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember_88CEE888FDAF5FC28908A3F6B9E9E3F4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_A2F9125AE59259EF887DA08474CCAF64" xlink:to="loc_us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember_88CEE888FDAF5FC28908A3F6B9E9E3F4" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_OtherAccruedLiabilitiesMember" xlink:label="loc_uis_OtherAccruedLiabilitiesMember_E168351393E453FD962D477F48506367" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_A2F9125AE59259EF887DA08474CCAF64" xlink:to="loc_uis_OtherAccruedLiabilitiesMember_E168351393E453FD962D477F48506367" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4555CA5632EA5AD0A975807CC9990CB6" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_50057BD99DC15347804E6307244955A1" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4555CA5632EA5AD0A975807CC9990CB6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C3ABB605E8C5004F84D6147D03A21299_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4555CA5632EA5AD0A975807CC9990CB6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C3ABB605E8C5004F84D6147D03A21299_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4647F000D7A551CFBDF9A98D8755FC31" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_4555CA5632EA5AD0A975807CC9990CB6" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4647F000D7A551CFBDF9A98D8755FC31" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_F82234579471586DB7BB3CFD46ED2B1D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_4647F000D7A551CFBDF9A98D8755FC31" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_F82234579471586DB7BB3CFD46ED2B1D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeAssets" xlink:label="loc_us-gaap_DerivativeAssets_FC6587B58F4557169897D18DA1553429" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_6945831C3A9D5B4CB8C77527B4729406" xlink:to="loc_us-gaap_DerivativeAssets_FC6587B58F4557169897D18DA1553429" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeLiabilities" xlink:label="loc_us-gaap_DerivativeLiabilities_C2652BE838245128BEEE27A4F76C9E98" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_6945831C3A9D5B4CB8C77527B4729406" xlink:to="loc_us-gaap_DerivativeLiabilities_C2652BE838245128BEEE27A4F76C9E98" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet" xlink:label="loc_us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet_5E31A7FA8870582B8B845FA129B6BB2D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_6945831C3A9D5B4CB8C77527B4729406" xlink:to="loc_us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet_5E31A7FA8870582B8B845FA129B6BB2D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsFairValuesOfOtherFinancialInstrumentsNotMeasuredAtFairValueInConsolidatedBalanceSheetsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_3E1907575BB9535FABB725669DF050C4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_967C449A53D45CAB86D2C3E178F854C9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_3E1907575BB9535FABB725669DF050C4" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_967C449A53D45CAB86D2C3E178F854C9" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueByMeasurementBasisAxis" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_9B4C145EA7EE5DA8A10F8A279F4909C4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_967C449A53D45CAB86D2C3E178F854C9" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_9B4C145EA7EE5DA8A10F8A279F4909C4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_2B850FCAAABCD60D998B147D0393849B_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_9B4C145EA7EE5DA8A10F8A279F4909C4" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_2B850FCAAABCD60D998B147D0393849B_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueDisclosureItemAmountsDomain" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_F671E876CF115C2CBE97A6C36682B2A3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_9B4C145EA7EE5DA8A10F8A279F4909C4" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_F671E876CF115C2CBE97A6C36682B2A3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_3A444E0790C851649228ADEB6DA138A1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_F671E876CF115C2CBE97A6C36682B2A3" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_3A444E0790C851649228ADEB6DA138A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_DF119428C90D506BA8AF27C02263890F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_F671E876CF115C2CBE97A6C36682B2A3" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_DF119428C90D506BA8AF27C02263890F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_97F9A558FD625C3F93BEB3753EC5052D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_967C449A53D45CAB86D2C3E178F854C9" xlink:to="loc_us-gaap_DebtInstrumentAxis_97F9A558FD625C3F93BEB3753EC5052D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_9484AB25A44CD864C675147D0394FD2E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_97F9A558FD625C3F93BEB3753EC5052D" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_9484AB25A44CD864C675147D0394FD2E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_A18842A854F65B5B8223BFA41B539D46" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_97F9A558FD625C3F93BEB3753EC5052D" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_A18842A854F65B5B8223BFA41B539D46" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TenPointSevenFivePercentageSeniorSecuredNotesDueinAprilTwoThousandTwentyTwoMember" xlink:label="loc_uis_TenPointSevenFivePercentageSeniorSecuredNotesDueinAprilTwoThousandTwentyTwoMember_829F3989EC7B5900996E7BCF65542B64" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_A18842A854F65B5B8223BFA41B539D46" xlink:to="loc_uis_TenPointSevenFivePercentageSeniorSecuredNotesDueinAprilTwoThousandTwentyTwoMember_829F3989EC7B5900996E7BCF65542B64" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ConvertibleSeniorNotesDue2021Member" xlink:label="loc_uis_ConvertibleSeniorNotesDue2021Member_22FDC845453D5FF6856F8DD9C0AD835B" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_A18842A854F65B5B8223BFA41B539D46" xlink:to="loc_uis_ConvertibleSeniorNotesDue2021Member_22FDC845453D5FF6856F8DD9C0AD835B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_F1CC8E158F64544CA41534EC591FA83D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_967C449A53D45CAB86D2C3E178F854C9" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_F1CC8E158F64544CA41534EC591FA83D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_DF7257E011BBC9BF6198147D0395D702_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_F1CC8E158F64544CA41534EC591FA83D" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_DF7257E011BBC9BF6198147D0395D702_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_85A3E09519205BB1B80776D5370013FD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_F1CC8E158F64544CA41534EC591FA83D" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_85A3E09519205BB1B80776D5370013FD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_A6A99CDCC0995FA7B24C584991B00A99" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_85A3E09519205BB1B80776D5370013FD" xlink:to="loc_us-gaap_SeniorNotesMember_A6A99CDCC0995FA7B24C584991B00A99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_1E8E6F30D8975BB690C81F43C6574FC8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_3E1907575BB9535FABB725669DF050C4" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_1E8E6F30D8975BB690C81F43C6574FC8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LongTermDebtFairValue" xlink:label="loc_us-gaap_LongTermDebtFairValue_F8C1CF2081C35427A0AA3A278FE99390" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_3E1907575BB9535FABB725669DF050C4" xlink:to="loc_us-gaap_LongTermDebtFairValue_F8C1CF2081C35427A0AA3A278FE99390" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_D10E43B1F5F05FFBA96FF5F3317C822D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_3E1907575BB9535FABB725669DF050C4" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_D10E43B1F5F05FFBA96FF5F3317C822D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsGainsAndLossesRecognizedOnForeignExchangeForwardContractsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_1533C51765265341B5BC8894C61FE8BB" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable" xlink:label="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_871B5FEBB2A25395938DA5B12C59E9E0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_1533C51765265341B5BC8894C61FE8BB" xlink:to="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_871B5FEBB2A25395938DA5B12C59E9E0" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_AD1440883C925AD2A1DE59F584932FA6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsTable_871B5FEBB2A25395938DA5B12C59E9E0" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_AD1440883C925AD2A1DE59F584932FA6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_027D79C494DBD4D898DE147D039A492C_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_AD1440883C925AD2A1DE59F584932FA6" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_027D79C494DBD4D898DE147D039A492C_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_542B5741398F5294A28D512424945897" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_AD1440883C925AD2A1DE59F584932FA6" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_542B5741398F5294A28D512424945897" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_OtherIncomeExpenseNetMember" xlink:label="loc_uis_OtherIncomeExpenseNetMember_DFC800AE9E37538DB63ED265CC9286A1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_542B5741398F5294A28D512424945897" xlink:to="loc_uis_OtherIncomeExpenseNetMember_DFC800AE9E37538DB63ED265CC9286A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnForeignCurrencyDerivativesRecordedInEarningsNet" xlink:label="loc_us-gaap_GainLossOnForeignCurrencyDerivativesRecordedInEarningsNet_8E7CDFFD87305D8BAAE7CF1BC16E2F65" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasuredOnRecurringBasisGainLossIncludedInEarningsAbstract_1533C51765265341B5BC8894C61FE8BB" xlink:to="loc_us-gaap_GainLossOnForeignCurrencyDerivativesRecordedInEarningsNet_8E7CDFFD87305D8BAAE7CF1BC16E2F65" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/FinancialInstrumentsAndFairValueMeasurementsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/Goodwill" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/GoodwillDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillLineItems" xlink:label="loc_us-gaap_GoodwillLineItems_93A72414D7425A0AB6D3381BA1C9A642" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfGoodwillTable" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_4A9423CEFE585FF3B50854614792752D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_93A72414D7425A0AB6D3381BA1C9A642" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_4A9423CEFE585FF3B50854614792752D" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis_2C0965501B1F5E25BECD957E30F5375C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_4A9423CEFE585FF3B50854614792752D" xlink:to="loc_srt_ProductOrServiceAxis_2C0965501B1F5E25BECD957E30F5375C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_D1BEC496C127CC81CE91147D03874B5E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_2C0965501B1F5E25BECD957E30F5375C" xlink:to="loc_srt_ProductsAndServicesDomain_D1BEC496C127CC81CE91147D03874B5E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_0D39A730E67D59DFB23FDEBF97D4105F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_2C0965501B1F5E25BECD957E30F5375C" xlink:to="loc_srt_ProductsAndServicesDomain_0D39A730E67D59DFB23FDEBF97D4105F" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_BusinessProcessOutsourcingServicesMember" xlink:label="loc_uis_BusinessProcessOutsourcingServicesMember_B4E88370C7AA59AEA0F9ABEE0C021535" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_0D39A730E67D59DFB23FDEBF97D4105F" xlink:to="loc_uis_BusinessProcessOutsourcingServicesMember_B4E88370C7AA59AEA0F9ABEE0C021535" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_70B791424B9F5938AFFA0933F073194B" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_4A9423CEFE585FF3B50854614792752D" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_70B791424B9F5938AFFA0933F073194B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_4B3C4DC06648185155A8147D0388D369_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_70B791424B9F5938AFFA0933F073194B" xlink:to="loc_us-gaap_SegmentDomain_4B3C4DC06648185155A8147D0388D369_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_3CB51C7521AD58BA9FD07B813A7EA910" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_70B791424B9F5938AFFA0933F073194B" xlink:to="loc_us-gaap_SegmentDomain_3CB51C7521AD58BA9FD07B813A7EA910" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ServicesMember" xlink:label="loc_uis_ServicesMember_AE3736C0648755A49CB213381612F425" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_3CB51C7521AD58BA9FD07B813A7EA910" xlink:to="loc_uis_ServicesMember_AE3736C0648755A49CB213381612F425" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_3D4CC93488055584BE51E9C44327802F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_93A72414D7425A0AB6D3381BA1C9A642" xlink:to="loc_us-gaap_Goodwill_3D4CC93488055584BE51E9C44327802F" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/GoodwillScheduleOfChangesInCarryingAmountOfGoodwillBySegmentDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillLineItems" xlink:label="loc_us-gaap_GoodwillLineItems_2BBA423D0ABC50408B050EBC2A6F493F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfGoodwillTable" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_F5F3B8E93C3D5FD9B5BBE96CBE71E6E1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_2BBA423D0ABC50408B050EBC2A6F493F" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_F5F3B8E93C3D5FD9B5BBE96CBE71E6E1" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_9A139206545E5D05A5CAD3FB0482D2DB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_F5F3B8E93C3D5FD9B5BBE96CBE71E6E1" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_9A139206545E5D05A5CAD3FB0482D2DB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_0025FE394C98FF0CA6F8147D0381B4FC_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_9A139206545E5D05A5CAD3FB0482D2DB" xlink:to="loc_us-gaap_SegmentDomain_0025FE394C98FF0CA6F8147D0381B4FC_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_80E46A83D0505A7E82DAE3B3819F2295" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_9A139206545E5D05A5CAD3FB0482D2DB" xlink:to="loc_us-gaap_SegmentDomain_80E46A83D0505A7E82DAE3B3819F2295" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ServicesMember" xlink:label="loc_uis_ServicesMember_6E18CF920B075921823A50C2C0C35994" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_80E46A83D0505A7E82DAE3B3819F2295" xlink:to="loc_uis_ServicesMember_6E18CF920B075921823A50C2C0C35994" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_C03DAFE2BFF85BBBA23AC2049B3A0E2F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_80E46A83D0505A7E82DAE3B3819F2295" xlink:to="loc_uis_TechnologyMember_C03DAFE2BFF85BBBA23AC2049B3A0E2F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillRollForward" xlink:label="loc_us-gaap_GoodwillRollForward_11F7F8F08E3A5575BEA1629856BB24DE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_2BBA423D0ABC50408B050EBC2A6F493F" xlink:to="loc_us-gaap_GoodwillRollForward_11F7F8F08E3A5575BEA1629856BB24DE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_E76F8DDCEE8255CA8DCFF066B9B82465" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_11F7F8F08E3A5575BEA1629856BB24DE" xlink:to="loc_us-gaap_Goodwill_E76F8DDCEE8255CA8DCFF066B9B82465" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_F55A326D1D8E549AA1E03F09524A3961" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_11F7F8F08E3A5575BEA1629856BB24DE" xlink:to="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_F55A326D1D8E549AA1E03F09524A3961" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/GoodwillTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/IncomeTaxes" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/IncomeTaxesDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/PensionAndPostretirementBenefits" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/PensionAndPostretirementBenefitsAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BF22CF9A255E5804BFB2CD348E11580E" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_42D13ED974235D41968154C6E6E0FB61" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BF22CF9A255E5804BFB2CD348E11580E" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_42D13ED974235D41968154C6E6E0FB61" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeAxis" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_92D6AC4F77075257A71A44120CB667D2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_42D13ED974235D41968154C6E6E0FB61" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_92D6AC4F77075257A71A44120CB667D2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_79177D54362C38FF0DD393D4766C7526_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_92D6AC4F77075257A71A44120CB667D2" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_79177D54362C38FF0DD393D4766C7526_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_AA94907032FF578FB7C220F5B3EB6632" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_92D6AC4F77075257A71A44120CB667D2" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_AA94907032FF578FB7C220F5B3EB6632" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionPlansDefinedBenefitMember" xlink:label="loc_us-gaap_PensionPlansDefinedBenefitMember_C8D11106679E5185B4F6F1430820F2B3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_AA94907032FF578FB7C220F5B3EB6632" xlink:to="loc_us-gaap_PensionPlansDefinedBenefitMember_C8D11106679E5185B4F6F1430820F2B3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:label="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_3073917E2A00502C885D5E2F7E73843E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_AA94907032FF578FB7C220F5B3EB6632" xlink:to="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_3073917E2A00502C885D5E2F7E73843E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationAxis" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationAxis_1058DC066DCC5C64BE86ECE64664465D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_42D13ED974235D41968154C6E6E0FB61" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationAxis_1058DC066DCC5C64BE86ECE64664465D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationDomain" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationDomain_91355FB02B016371F68993D4766D39B7_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationAxis_1058DC066DCC5C64BE86ECE64664465D" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationDomain_91355FB02B016371F68993D4766D39B7_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationDomain" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationDomain_023CA208FE405A11BB9CE8A8C9E6796C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationAxis_1058DC066DCC5C64BE86ECE64664465D" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationDomain_023CA208FE405A11BB9CE8A8C9E6796C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_C1DC61474FA458DDA2F6A9782BE97AF6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationDomain_023CA208FE405A11BB9CE8A8C9E6796C" xlink:to="loc_country_US_C1DC61474FA458DDA2F6A9782BE97AF6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignPlanMember" xlink:label="loc_us-gaap_ForeignPlanMember_49FDDFE689FF5656AFF34C3C20E381C9" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationDomain_023CA208FE405A11BB9CE8A8C9E6796C" xlink:to="loc_us-gaap_ForeignPlanMember_49FDDFE689FF5656AFF34C3C20E381C9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsCurrentFiscalYear" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsCurrentFiscalYear_6AC39AA09D1152BC8308D83460F5927A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BF22CF9A255E5804BFB2CD348E11580E" xlink:to="loc_us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsCurrentFiscalYear_6AC39AA09D1152BC8308D83460F5927A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionContributions" xlink:label="loc_us-gaap_PensionContributions_D2CFA2DD34C956BEA6F76F611C2005AB" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BF22CF9A255E5804BFB2CD348E11580E" xlink:to="loc_us-gaap_PensionContributions_D2CFA2DD34C956BEA6F76F611C2005AB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherPostretirementBenefitsPayments" xlink:label="loc_us-gaap_OtherPostretirementBenefitsPayments_4DBCF573E7005B9DB2C1C44887E1B10B" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_BF22CF9A255E5804BFB2CD348E11580E" xlink:to="loc_us-gaap_OtherPostretirementBenefitsPayments_4DBCF573E7005B9DB2C1C44887E1B10B" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/PensionAndPostretirementBenefitsComponentsOfNetPeriodicBenefitExpenseDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:label="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_23F6463269285173BD05690CEE1AFD17" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_23F6463269285173BD05690CEE1AFD17" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeAxis" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_5B4156035DBD5066BE4389A8311AE99C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_23F6463269285173BD05690CEE1AFD17" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_5B4156035DBD5066BE4389A8311AE99C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_30979F5BAC007D351A41633E2FCDC8D1_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_5B4156035DBD5066BE4389A8311AE99C" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_30979F5BAC007D351A41633E2FCDC8D1_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_B552BA6B392E5070B7FCE3E98D21F466" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_5B4156035DBD5066BE4389A8311AE99C" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_B552BA6B392E5070B7FCE3E98D21F466" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionPlansDefinedBenefitMember" xlink:label="loc_us-gaap_PensionPlansDefinedBenefitMember_8A5145F4207E5EBF95DC13C66D54C0D8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_B552BA6B392E5070B7FCE3E98D21F466" xlink:to="loc_us-gaap_PensionPlansDefinedBenefitMember_8A5145F4207E5EBF95DC13C66D54C0D8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:label="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_54641AF8824D54D78620F597B55BD36A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_B552BA6B392E5070B7FCE3E98D21F466" xlink:to="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_54641AF8824D54D78620F597B55BD36A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationAxis" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationAxis_8EF5E26D35E959B78FF10CDF0AF9D781" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_23F6463269285173BD05690CEE1AFD17" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationAxis_8EF5E26D35E959B78FF10CDF0AF9D781" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationDomain" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationDomain_72A9BC8248400D489A80633E2FCE2D9D_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationAxis_8EF5E26D35E959B78FF10CDF0AF9D781" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationDomain_72A9BC8248400D489A80633E2FCE2D9D_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanSponsorLocationDomain" xlink:label="loc_us-gaap_RetirementPlanSponsorLocationDomain_3E6FB057BBBC5C58872AF27AF0E1EEE5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationAxis_8EF5E26D35E959B78FF10CDF0AF9D781" xlink:to="loc_us-gaap_RetirementPlanSponsorLocationDomain_3E6FB057BBBC5C58872AF27AF0E1EEE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_68DD2A3410585DEAA563970EC49D26BA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationDomain_3E6FB057BBBC5C58872AF27AF0E1EEE5" xlink:to="loc_country_US_68DD2A3410585DEAA563970EC49D26BA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignPlanMember" xlink:label="loc_us-gaap_ForeignPlanMember_DA927A75F9455BD2B827C79403ABCA1D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanSponsorLocationDomain_3E6FB057BBBC5C58872AF27AF0E1EEE5" xlink:to="loc_us-gaap_ForeignPlanMember_DA927A75F9455BD2B827C79403ABCA1D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanServiceCost" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost_194BC2F7F5B75779B6DA39EA72F1E2DF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_DefinedBenefitPlanServiceCost_194BC2F7F5B75779B6DA39EA72F1E2DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanInterestCost" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost_F508C0FD20A250C2A5D6571375AD3645" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_DefinedBenefitPlanInterestCost_F508C0FD20A250C2A5D6571375AD3645" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_7E3F4B7349BC5A1BBE973522E823AA31" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_7E3F4B7349BC5A1BBE973522E823AA31" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_D65373EA0E09587698F4845814B4B46D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_D65373EA0E09587698F4845814B4B46D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_D58BF29E79BF5E8BA35366CB0AE9F566" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_D58BF29E79BF5E8BA35366CB0AE9F566" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments" xlink:label="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_DDD47355833B5692A433CC970305C0ED" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments_DDD47355833B5692A433CC970305C0ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F2B39116073250BDB35516E1154B8482" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_0EE85CC71697597BB9309897455D3AE0" xlink:to="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_F2B39116073250BDB35516E1154B8482" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/PensionAndPostretirementBenefitsTables" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:label="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_D7F4DC75D72E52BBB996DCF7EB1FB9DC" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_9DB660E2C26A50A99446E4C6554F901C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_D7F4DC75D72E52BBB996DCF7EB1FB9DC" xlink:to="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_9DB660E2C26A50A99446E4C6554F901C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeAxis" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_BB6516CCB508519B948D3FB44FA9180D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_9DB660E2C26A50A99446E4C6554F901C" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_BB6516CCB508519B948D3FB44FA9180D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_CA2C864790A25CB320FE93D476A43A3E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_BB6516CCB508519B948D3FB44FA9180D" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_CA2C864790A25CB320FE93D476A43A3E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RetirementPlanTypeDomain" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_2449CC6E589A5D318A73E9736DBE0687" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_BB6516CCB508519B948D3FB44FA9180D" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_2449CC6E589A5D318A73E9736DBE0687" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PensionPlansDefinedBenefitMember" xlink:label="loc_us-gaap_PensionPlansDefinedBenefitMember_A820FDCDEC605D40A81E0E2A748DF52B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_2449CC6E589A5D318A73E9736DBE0687" xlink:to="loc_us-gaap_PensionPlansDefinedBenefitMember_A820FDCDEC605D40A81E0E2A748DF52B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:label="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_952C8DD7AFFD52B6949ACD9E2AB45E80" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_2449CC6E589A5D318A73E9736DBE0687" xlink:to="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_952C8DD7AFFD52B6949ACD9E2AB45E80" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_DCEBC993FDF5579F9C8DED6748FADA9D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems_D7F4DC75D72E52BBB996DCF7EB1FB9DC" xlink:to="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_DCEBC993FDF5579F9C8DED6748FADA9D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/Properties" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/PropertiesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_05879B127984C9507E1C8E17716DF7A7" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_89B1C02373349A2813F98E17716B1CF4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_05879B127984C9507E1C8E17716DF7A7" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_89B1C02373349A2813F98E17716B1CF4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_58D6D6EBA242759191598E17716B667D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_89B1C02373349A2813F98E17716B1CF4" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_58D6D6EBA242759191598E17716B667D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_167E02319D1A47293FB58E17716CBDD0_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_58D6D6EBA242759191598E17716B667D" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_167E02319D1A47293FB58E17716CBDD0_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_167E02319D1A47293FB58E17716CBDD0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_58D6D6EBA242759191598E17716B667D" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_167E02319D1A47293FB58E17716CBDD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LandAndBuildingMember" xlink:label="loc_us-gaap_LandAndBuildingMember_4642AC489E080CEE1EF68E17716C24E4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_167E02319D1A47293FB58E17716CBDD0" xlink:to="loc_us-gaap_LandAndBuildingMember_4642AC489E080CEE1EF68E17716C24E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srt_StatementGeographicalAxis_5B8586FF19FECAE79FDF8E17716C83D0" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_89B1C02373349A2813F98E17716B1CF4" xlink:to="loc_srt_StatementGeographicalAxis_5B8586FF19FECAE79FDF8E17716C83D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_8B71EA236461295B001B8E17716D1B7F_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_5B8586FF19FECAE79FDF8E17716C83D0" xlink:to="loc_srt_SegmentGeographicalDomain_8B71EA236461295B001B8E17716D1B7F_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_8B71EA236461295B001B8E17716D1B7F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_5B8586FF19FECAE79FDF8E17716C83D0" xlink:to="loc_srt_SegmentGeographicalDomain_8B71EA236461295B001B8E17716D1B7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_GB" xlink:label="loc_country_GB_5622221069D7318EF6AC8E17716DA290" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_8B71EA236461295B001B8E17716D1B7F" xlink:to="loc_country_GB_5622221069D7318EF6AC8E17716DA290" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_A0987A0EC6DE3F8E5DEA8E17716DDFCD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_05879B127984C9507E1C8E17716DF7A7" xlink:to="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_A0987A0EC6DE3F8E5DEA8E17716DDFCD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:label="loc_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_F902E551F165A6DD816D8E17716EE171" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_05879B127984C9507E1C8E17716DF7A7" xlink:to="loc_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_F902E551F165A6DD816D8E17716EE171" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/SegmentInformation" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/SegmentInformationAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_E3823EF23702E03DEBF91274D3FA94B7" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_4AE833AB34A7005D0D4F1274D3F714F3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_E3823EF23702E03DEBF91274D3FA94B7" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_4AE833AB34A7005D0D4F1274D3F714F3" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_8B37A6FE243AE6188B551274D3F73914" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_4AE833AB34A7005D0D4F1274D3F714F3" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_8B37A6FE243AE6188B551274D3F73914" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_15C546552AD00E8A8B731274D3F7F5A1_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_8B37A6FE243AE6188B551274D3F73914" xlink:to="loc_us-gaap_SegmentDomain_15C546552AD00E8A8B731274D3F7F5A1_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_15C546552AD00E8A8B731274D3F7F5A1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_8B37A6FE243AE6188B551274D3F73914" xlink:to="loc_us-gaap_SegmentDomain_15C546552AD00E8A8B731274D3F7F5A1" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_945BFE9F4895F9397BE01274D3F8105A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_15C546552AD00E8A8B731274D3F7F5A1" xlink:to="loc_uis_TechnologyMember_945BFE9F4895F9397BE01274D3F8105A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis_D38740D1550A212CA5E41274D3F8378C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_4AE833AB34A7005D0D4F1274D3F714F3" xlink:to="loc_srt_ProductOrServiceAxis_D38740D1550A212CA5E41274D3F8378C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_A7CBD80E08644817A3421274D3F877D6_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_D38740D1550A212CA5E41274D3F8378C" xlink:to="loc_srt_ProductsAndServicesDomain_A7CBD80E08644817A3421274D3F877D6_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_A7CBD80E08644817A3421274D3F877D6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_D38740D1550A212CA5E41274D3F8378C" xlink:to="loc_srt_ProductsAndServicesDomain_A7CBD80E08644817A3421274D3F877D6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_LicenseAndMaintenanceMember" xlink:label="loc_us-gaap_LicenseAndMaintenanceMember_84084B709B89CFCF19581274D3F98AAE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_A7CBD80E08644817A3421274D3F877D6" xlink:to="loc_us-gaap_LicenseAndMaintenanceMember_84084B709B89CFCF19581274D3F98AAE" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_OtherTechnologyMember" xlink:label="loc_uis_OtherTechnologyMember_80BDF8CC999300CDB90D1274D3F94CF5" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_A7CBD80E08644817A3421274D3F877D6" xlink:to="loc_uis_OtherTechnologyMember_80BDF8CC999300CDB90D1274D3F94CF5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_6D09346C2C4548153EBB1274D3F95A08" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_4AE833AB34A7005D0D4F1274D3F714F3" xlink:to="loc_srt_ConsolidationItemsAxis_6D09346C2C4548153EBB1274D3F95A08" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_36BBA43652419F2A63B61274D3F99911_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_6D09346C2C4548153EBB1274D3F95A08" xlink:to="loc_srt_ConsolidationItemsDomain_36BBA43652419F2A63B61274D3F99911_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_36BBA43652419F2A63B61274D3F99911" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_6D09346C2C4548153EBB1274D3F95A08" xlink:to="loc_srt_ConsolidationItemsDomain_36BBA43652419F2A63B61274D3F99911" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MaterialReconcilingItemsMember" xlink:label="loc_us-gaap_MaterialReconcilingItemsMember_CC3FE2C963F3FEFD4CDE1274D3F9BBEE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_36BBA43652419F2A63B61274D3F99911" xlink:to="loc_us-gaap_MaterialReconcilingItemsMember_CC3FE2C963F3FEFD4CDE1274D3F9BBEE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_4FEB3AE54455D04F28851274D3FACA48" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_E3823EF23702E03DEBF91274D3FA94B7" xlink:to="loc_us-gaap_Revenues_4FEB3AE54455D04F28851274D3FACA48" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="loc_us-gaap_NumberOfOperatingSegments_8E2DDB359C3D97CB0B961274D3FADFF7" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_E3823EF23702E03DEBF91274D3FA94B7" xlink:to="loc_us-gaap_NumberOfOperatingSegments_8E2DDB359C3D97CB0B961274D3FADFF7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_450D4D9B091628351FD61274D3FB9698" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_E3823EF23702E03DEBF91274D3FA94B7" xlink:to="loc_us-gaap_OperatingIncomeLoss_450D4D9B091628351FD61274D3FB9698" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/SegmentInformationCustomerRevenueByClassesOfSimilarProductsOrServicesDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems" xlink:label="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_159F1639D109575490611837D23212BD" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_3265ABB1184E5156AA516274AAA105D3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_159F1639D109575490611837D23212BD" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_3265ABB1184E5156AA516274AAA105D3" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis_55A8D96E9C49533291CB3D4ED70BEBD2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_3265ABB1184E5156AA516274AAA105D3" xlink:to="loc_srt_ProductOrServiceAxis_55A8D96E9C49533291CB3D4ED70BEBD2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_054ABA3D368CBB78E88E147D02F7F59E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_55A8D96E9C49533291CB3D4ED70BEBD2" xlink:to="loc_srt_ProductsAndServicesDomain_054ABA3D368CBB78E88E147D02F7F59E_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_B8293C2431EF5DA095F044815444A4FA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_55A8D96E9C49533291CB3D4ED70BEBD2" xlink:to="loc_srt_ProductsAndServicesDomain_B8293C2431EF5DA095F044815444A4FA" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_CloudAndInfrastructureServicesMember" xlink:label="loc_uis_CloudAndInfrastructureServicesMember_603BC554907E5FA7972E5090336F9DAB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_B8293C2431EF5DA095F044815444A4FA" xlink:to="loc_uis_CloudAndInfrastructureServicesMember_603BC554907E5FA7972E5090336F9DAB" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ApplicationServicesMember" xlink:label="loc_uis_ApplicationServicesMember_30F4782AF4C7530AA19CF2E0532CCD82" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_B8293C2431EF5DA095F044815444A4FA" xlink:to="loc_uis_ApplicationServicesMember_30F4782AF4C7530AA19CF2E0532CCD82" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_BusinessProcessOutsourcingServicesMember" xlink:label="loc_uis_BusinessProcessOutsourcingServicesMember_CCD300C9694A559A8AA2B8B6F880685E" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_B8293C2431EF5DA095F044815444A4FA" xlink:to="loc_uis_BusinessProcessOutsourcingServicesMember_CCD300C9694A559A8AA2B8B6F880685E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_F5DFB10032FC5363A10B6DB25FA6E91E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_3265ABB1184E5156AA516274AAA105D3" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_F5DFB10032FC5363A10B6DB25FA6E91E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_2641064290BDA974C81B147D02F8CB77_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_F5DFB10032FC5363A10B6DB25FA6E91E" xlink:to="loc_us-gaap_SegmentDomain_2641064290BDA974C81B147D02F8CB77_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_00F990BD8B3E5DCAB07BA6A331635F9B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_F5DFB10032FC5363A10B6DB25FA6E91E" xlink:to="loc_us-gaap_SegmentDomain_00F990BD8B3E5DCAB07BA6A331635F9B" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ServicesMember" xlink:label="loc_uis_ServicesMember_707254C928875B1A9A75E198E85443A9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_00F990BD8B3E5DCAB07BA6A331635F9B" xlink:to="loc_uis_ServicesMember_707254C928875B1A9A75E198E85443A9" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_14895196269F5EF4B7C32E873EA7CB58" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_00F990BD8B3E5DCAB07BA6A331635F9B" xlink:to="loc_uis_TechnologyMember_14895196269F5EF4B7C32E873EA7CB58" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_4F7A537D99ED5436916A9FE8D0AD23C8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_159F1639D109575490611837D23212BD" xlink:to="loc_us-gaap_Revenues_4F7A537D99ED5436916A9FE8D0AD23C8" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/SegmentInformationReconciliationOfSegmentOperatingIncomeToConsolidatedLossBeforeIncomeTaxesDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems" xlink:label="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_ECBFDDC4272243194B3084E0AA663F7D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable" xlink:label="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_91CD688FE308C0FBE08A84E0AA63497F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_ECBFDDC4272243194B3084E0AA663F7D" xlink:to="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_91CD688FE308C0FBE08A84E0AA63497F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_074F12218144A0761BF384E0AA638923" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_91CD688FE308C0FBE08A84E0AA63497F" xlink:to="loc_srt_ConsolidationItemsAxis_074F12218144A0761BF384E0AA638923" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_FC22A0FDF3F291497EB384E0AA647F2B_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_074F12218144A0761BF384E0AA638923" xlink:to="loc_srt_ConsolidationItemsDomain_FC22A0FDF3F291497EB384E0AA647F2B_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_FC22A0FDF3F291497EB384E0AA647F2B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_074F12218144A0761BF384E0AA638923" xlink:to="loc_srt_ConsolidationItemsDomain_FC22A0FDF3F291497EB384E0AA647F2B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember_6528049F9624971480C984E0AA64EAAB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_FC22A0FDF3F291497EB384E0AA647F2B" xlink:to="loc_us-gaap_OperatingSegmentsMember_6528049F9624971480C984E0AA64EAAB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_MaterialReconcilingItemsMember" xlink:label="loc_us-gaap_MaterialReconcilingItemsMember_4259E0A2CE7E64491BFE84E0AA643FC5" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_FC22A0FDF3F291497EB384E0AA647F2B" xlink:to="loc_us-gaap_MaterialReconcilingItemsMember_4259E0A2CE7E64491BFE84E0AA643FC5" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_CorporateAndReconcilingItemsMember" xlink:label="loc_uis_CorporateAndReconcilingItemsMember_12FBD5E6ADE92FE4B70C84E0AA651785" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_FC22A0FDF3F291497EB384E0AA647F2B" xlink:to="loc_uis_CorporateAndReconcilingItemsMember_12FBD5E6ADE92FE4B70C84E0AA651785" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_FA3D499C006CCAB4394B84E0AA657163" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_91CD688FE308C0FBE08A84E0AA63497F" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_FA3D499C006CCAB4394B84E0AA657163" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_13EB03401A188DCE1ACB84E0AA65C414_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_FA3D499C006CCAB4394B84E0AA657163" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_13EB03401A188DCE1ACB84E0AA65C414_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_13EB03401A188DCE1ACB84E0AA65C414" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_FA3D499C006CCAB4394B84E0AA657163" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_13EB03401A188DCE1ACB84E0AA65C414" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpenseMember" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_CAA361935413423861B684E0AA65CF70" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_13EB03401A188DCE1ACB84E0AA65C414" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpenseMember_CAA361935413423861B684E0AA65CF70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCostAndReserveAxis" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_C23F43AA66C07A51404D84E0AA66632A" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTable_91CD688FE308C0FBE08A84E0AA63497F" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_C23F43AA66C07A51404D84E0AA66632A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_1B2F9FAA4C6C223DBA9A84E0AA66BF36_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_C23F43AA66C07A51404D84E0AA66632A" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_1B2F9FAA4C6C223DBA9A84E0AA66BF36_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_1B2F9FAA4C6C223DBA9A84E0AA66BF36" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_C23F43AA66C07A51404D84E0AA66632A" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_1B2F9FAA4C6C223DBA9A84E0AA66BF36" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ForeignCurrencyTranslationAdjustmentMember" xlink:label="loc_uis_ForeignCurrencyTranslationAdjustmentMember_EAE07E41A67416B29D8384E0AA669798" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_1B2F9FAA4C6C223DBA9A84E0AA66BF36" xlink:to="loc_uis_ForeignCurrencyTranslationAdjustmentMember_EAE07E41A67416B29D8384E0AA669798" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_A7D5872F34FA6CB81E5E84E0AA664FE5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_ECBFDDC4272243194B3084E0AA663F7D" xlink:to="loc_us-gaap_OperatingIncomeLoss_A7D5872F34FA6CB81E5E84E0AA664FE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_D2D69BAFA307D81CAF1384E0AA67366A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_ECBFDDC4272243194B3084E0AA663F7D" xlink:to="loc_us-gaap_InterestExpense_D2D69BAFA307D81CAF1384E0AA67366A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_ABFC62D6E8FF38C9935484E0AA674661" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_ECBFDDC4272243194B3084E0AA663F7D" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_ABFC62D6E8FF38C9935484E0AA674661" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_184039AE136E96224E6F84E0AA67255C" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_ECBFDDC4272243194B3084E0AA663F7D" xlink:to="loc_us-gaap_RestructuringCharges_184039AE136E96224E6F84E0AA67255C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_0A6F8ADC154AC1C5AD1B84E0AA67B4A8" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingReconcilingItemForOperatingProfitLossFromSegmentToConsolidatedLineItems_ECBFDDC4272243194B3084E0AA663F7D" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_0A6F8ADC154AC1C5AD1B84E0AA67B4A8" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/SegmentInformationRevenuePropertiesAndOutsourcingAssetsByGeographicSegmentDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_32A8A0A1A7D953B4A15F043B1F4EE570" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_233948FE5BFB54AEB16E95BA955831F6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_32A8A0A1A7D953B4A15F043B1F4EE570" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_233948FE5BFB54AEB16E95BA955831F6" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srt_StatementGeographicalAxis_B617F121D1755EA9A3476B7ED068B1B7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_233948FE5BFB54AEB16E95BA955831F6" xlink:to="loc_srt_StatementGeographicalAxis_B617F121D1755EA9A3476B7ED068B1B7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_2785055D4A70E35B2AC8147D02F04376_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_B617F121D1755EA9A3476B7ED068B1B7" xlink:to="loc_srt_SegmentGeographicalDomain_2785055D4A70E35B2AC8147D02F04376_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_F2E39EDA4D935DABB0B8C4A083DB9238" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_B617F121D1755EA9A3476B7ED068B1B7" xlink:to="loc_srt_SegmentGeographicalDomain_F2E39EDA4D935DABB0B8C4A083DB9238" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_BE840EB249625C2C9CD042452B945691" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_F2E39EDA4D935DABB0B8C4A083DB9238" xlink:to="loc_country_US_BE840EB249625C2C9CD042452B945691" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_GB" xlink:label="loc_country_GB_CB2615ED1D6652C4BF6E62255D53AABF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_F2E39EDA4D935DABB0B8C4A083DB9238" xlink:to="loc_country_GB_CB2615ED1D6652C4BF6E62255D53AABF" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_OtherInternationalMember" xlink:label="loc_uis_OtherInternationalMember_49F4E145F76951A79137C834EF69DCD8" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_F2E39EDA4D935DABB0B8C4A083DB9238" xlink:to="loc_uis_OtherInternationalMember_49F4E145F76951A79137C834EF69DCD8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_5AE10A378A9E588EAB99E1466ACA24AA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_32A8A0A1A7D953B4A15F043B1F4EE570" xlink:to="loc_us-gaap_Revenues_5AE10A378A9E588EAB99E1466ACA24AA" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/SegmentInformationSummaryOfOperationsBySegmentDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_9B406777DDFDCF09BF738E17703C9EBC" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_071AA176D9D33B1005E18E1770386410" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_9B406777DDFDCF09BF738E17703C9EBC" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_071AA176D9D33B1005E18E1770386410" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_5BF3E19A84E0A917907B8E1770392B3C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_071AA176D9D33B1005E18E1770386410" xlink:to="loc_srt_ConsolidationItemsAxis_5BF3E19A84E0A917907B8E1770392B3C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_10DBEEA386F30DCB62AE8E177039DCE6_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_5BF3E19A84E0A917907B8E1770392B3C" xlink:to="loc_srt_ConsolidationItemsDomain_10DBEEA386F30DCB62AE8E177039DCE6_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_10DBEEA386F30DCB62AE8E177039DCE6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_5BF3E19A84E0A917907B8E1770392B3C" xlink:to="loc_srt_ConsolidationItemsDomain_10DBEEA386F30DCB62AE8E177039DCE6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="loc_us-gaap_IntersegmentEliminationMember_E10B1ACC77F9FFF8DDD08E17703A7254" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_10DBEEA386F30DCB62AE8E177039DCE6" xlink:to="loc_us-gaap_IntersegmentEliminationMember_E10B1ACC77F9FFF8DDD08E17703A7254" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember_F6E854B33491708D7BCF8E17703BF24D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_10DBEEA386F30DCB62AE8E177039DCE6" xlink:to="loc_us-gaap_OperatingSegmentsMember_F6E854B33491708D7BCF8E17703BF24D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CorporateNonSegmentMember" xlink:label="loc_us-gaap_CorporateNonSegmentMember_78644A42081D92D723B98E17703B5170" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_10DBEEA386F30DCB62AE8E177039DCE6" xlink:to="loc_us-gaap_CorporateNonSegmentMember_78644A42081D92D723B98E17703B5170" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_CEBEDD87210681A9627A8E17703B8ACB" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_071AA176D9D33B1005E18E1770386410" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_CEBEDD87210681A9627A8E17703B8ACB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_001C827666C4A126BE568E17703B31EE_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_CEBEDD87210681A9627A8E17703B8ACB" xlink:to="loc_us-gaap_SegmentDomain_001C827666C4A126BE568E17703B31EE_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_001C827666C4A126BE568E17703B31EE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_CEBEDD87210681A9627A8E17703B8ACB" xlink:to="loc_us-gaap_SegmentDomain_001C827666C4A126BE568E17703B31EE" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ServicesMember" xlink:label="loc_uis_ServicesMember_EE3C302C5F1051F96FDF8E17703C8144" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_001C827666C4A126BE568E17703B31EE" xlink:to="loc_uis_ServicesMember_EE3C302C5F1051F96FDF8E17703C8144" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_F6071722E77CF695E0D28E17703C6A86" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_001C827666C4A126BE568E17703B31EE" xlink:to="loc_uis_TechnologyMember_F6071722E77CF695E0D28E17703C6A86" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_28F270577A8BC5EB37098E17703DE4E8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_9B406777DDFDCF09BF738E17703C9EBC" xlink:to="loc_us-gaap_Revenues_28F270577A8BC5EB37098E17703DE4E8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_999FF26EAED7BE6EA10E8E17703D6967" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_9B406777DDFDCF09BF738E17703C9EBC" xlink:to="loc_us-gaap_OperatingIncomeLoss_999FF26EAED7BE6EA10E8E17703D6967" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/SegmentInformationTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/StockCompensation" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/StockCompensationAdditionalInformationDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_E8CDF9B6BD3E87040F941274D54748C4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_E8CDF9B6BD3E87040F941274D54748C4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_73D2A2B294224FDE35671274D5485DF6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_E8CDF9B6BD3E87040F941274D54748C4" xlink:to="loc_us-gaap_AwardTypeAxis_73D2A2B294224FDE35671274D5485DF6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E8D93FB76B7BCAAABAA01274D5481201_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_73D2A2B294224FDE35671274D5485DF6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E8D93FB76B7BCAAABAA01274D5481201_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E8D93FB76B7BCAAABAA01274D5481201" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_73D2A2B294224FDE35671274D5485DF6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E8D93FB76B7BCAAABAA01274D5481201" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_11F3241892ED3D8C6ADF1274D5487D9A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E8D93FB76B7BCAAABAA01274D5481201" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_11F3241892ED3D8C6ADF1274D5487D9A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_698028168493F236B3701274D5480CC7" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E8D93FB76B7BCAAABAA01274D5481201" xlink:to="loc_us-gaap_EmployeeStockOptionMember_698028168493F236B3701274D5480CC7" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_PerformanceBasedUnitMember" xlink:label="loc_uis_PerformanceBasedUnitMember_3281A4C8D12F89427B771274D5492C5C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E8D93FB76B7BCAAABAA01274D5481201" xlink:to="loc_uis_PerformanceBasedUnitMember_3281A4C8D12F89427B771274D5492C5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_2DA270AE3D52549144D51274D549F24F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_E8CDF9B6BD3E87040F941274D54748C4" xlink:to="loc_srt_RangeAxis_2DA270AE3D52549144D51274D549F24F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_F877E3871FF6329DAE451274D5499398_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_2DA270AE3D52549144D51274D549F24F" xlink:to="loc_srt_RangeMember_F877E3871FF6329DAE451274D5499398_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_F877E3871FF6329DAE451274D5499398" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_2DA270AE3D52549144D51274D549F24F" xlink:to="loc_srt_RangeMember_F877E3871FF6329DAE451274D5499398" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_5C38BF4F693C4D60E61A1274D5498EAC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_F877E3871FF6329DAE451274D5499398" xlink:to="loc_srt_MinimumMember_5C38BF4F693C4D60E61A1274D5498EAC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_FF7D2D6559F450DE4DA01274D54AAD00" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_F877E3871FF6329DAE451274D5499398" xlink:to="loc_srt_MaximumMember_FF7D2D6559F450DE4DA01274D54AAD00" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_4A877DA5B2C46D48818C1274D54AE96E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_4A877DA5B2C46D48818C1274D54AE96E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_0A6B229704145035DAF31274D54B4B1C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_0A6B229704145035DAF31274D54B4B1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_205B4E209786D58FD0DF1274D54BF0BC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_205B4E209786D58FD0DF1274D54BF0BC" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesVestingAfterAchievementOfGoals" xlink:label="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesVestingAfterAchievementOfGoals_5C058C29892857AB3DBC1274D54B3D05" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesVestingAfterAchievementOfGoals_5C058C29892857AB3DBC1274D54B3D05" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_14308907F961452F63AA1274D54B362E" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_14308907F961452F63AA1274D54B362E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_0B09CC8D47595B093B371274D54C0819" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_0B09CC8D47595B093B371274D54C0819" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_EE3238FD7F196E5FB29E1274D54C0B3A" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_EE3238FD7F196E5FB29E1274D54C0B3A" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_C2F329133292ECB509091274D54C6781" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_C3F716D081997939DA991274D54AAF0A" xlink:to="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_C2F329133292ECB509091274D54C6781" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/StockCompensationStockCompensationWeightedAverageAssumptionsDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/StockCompensationSummaryOfRestrictedStockUnitActivityDetail" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DE67FBDB339A577BB57F57E0C4F4816C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_57A125B9AB4E5CFC9BA48C4B540A51BB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DE67FBDB339A577BB57F57E0C4F4816C" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_57A125B9AB4E5CFC9BA48C4B540A51BB" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_262C76DE1C2756F1BE76C309F6910FDF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_57A125B9AB4E5CFC9BA48C4B540A51BB" xlink:to="loc_us-gaap_AwardTypeAxis_262C76DE1C2756F1BE76C309F6910FDF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E6ABAED229589655121F147D03CD69A4_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_262C76DE1C2756F1BE76C309F6910FDF" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_E6ABAED229589655121F147D03CD69A4_D5AD15D2D05E5B83A07CDB7FB7BFA30F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5832BF7C6BA152F9B75B50BA30B41C58" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_262C76DE1C2756F1BE76C309F6910FDF" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5832BF7C6BA152F9B75B50BA30B41C58" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_CF34C1A6C4D75A70AA2A8C404F65420B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_5832BF7C6BA152F9B75B50BA30B41C58" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_CF34C1A6C4D75A70AA2A8C404F65420B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_AB47A45714E75352A293DF8DCCF03289" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DE67FBDB339A577BB57F57E0C4F4816C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_AB47A45714E75352A293DF8DCCF03289" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_AA9414E460735D2AB3E5D257010445F7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_AB47A45714E75352A293DF8DCCF03289" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_AA9414E460735D2AB3E5D257010445F7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_A136BEA804E759C0AFE8C71791374FC9" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_AB47A45714E75352A293DF8DCCF03289" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_A136BEA804E759C0AFE8C71791374FC9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_F82B14B8B3525381987F88E77128BE22" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_AB47A45714E75352A293DF8DCCF03289" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_F82B14B8B3525381987F88E77128BE22" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpirationsInPeriod" xlink:label="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpirationsInPeriod_BA03C2941FED5CB1B90A310ED05E489E" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_AB47A45714E75352A293DF8DCCF03289" xlink:to="loc_uis_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresAndExpirationsInPeriod_BA03C2941FED5CB1B90A310ED05E489E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_5946B8AF8D855FD8892373AD88ECAB90" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DE67FBDB339A577BB57F57E0C4F4816C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_5946B8AF8D855FD8892373AD88ECAB90" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_2EC4BABE240F5284A9C5B09A74AE7878" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_5946B8AF8D855FD8892373AD88ECAB90" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue_2EC4BABE240F5284A9C5B09A74AE7878" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_124F308DF1145218B1E69BC0F211B4A1" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_5946B8AF8D855FD8892373AD88ECAB90" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_124F308DF1145218B1E69BC0F211B4A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_B9BC194029D4567894AAAE716A8AB841" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_5946B8AF8D855FD8892373AD88ECAB90" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue_B9BC194029D4567894AAAE716A8AB841" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_4406B6E63D9E525D803325A10474F395" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_5946B8AF8D855FD8892373AD88ECAB90" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue_4406B6E63D9E525D803325A10474F395" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/StockCompensationSummaryOfStockOptionActivityDetail" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/StockCompensationTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/SummaryOfSignificantAccountingPolicies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/SummaryOfSignificantAccountingPoliciesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalizedContractCostLineItems" xlink:label="loc_us-gaap_CapitalizedContractCostLineItems_172A82ABF01D507AB9EB533C4CD86C02" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalizedContractCostTable" xlink:label="loc_us-gaap_CapitalizedContractCostTable_0ABC0CEE6E76540AA4B6BB2BB74DF55F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_172A82ABF01D507AB9EB533C4CD86C02" xlink:to="loc_us-gaap_CapitalizedContractCostTable_0ABC0CEE6E76540AA4B6BB2BB74DF55F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_090F140188615D8AB085EB44899E2BDB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CapitalizedContractCostTable_0ABC0CEE6E76540AA4B6BB2BB74DF55F" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_090F140188615D8AB085EB44899E2BDB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_A81170EAC9CAC5F3FB788748160D4543_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_090F140188615D8AB085EB44899E2BDB" xlink:to="loc_us-gaap_SegmentDomain_A81170EAC9CAC5F3FB788748160D4543_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_FBF2BA3282625D30B1BC52367D3CE446" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_090F140188615D8AB085EB44899E2BDB" xlink:to="loc_us-gaap_SegmentDomain_FBF2BA3282625D30B1BC52367D3CE446" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_TechnologyMember" xlink:label="loc_uis_TechnologyMember_A8278935462C5D458AC0E11797CA83F6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_FBF2BA3282625D30B1BC52367D3CE446" xlink:to="loc_uis_TechnologyMember_A8278935462C5D458AC0E11797CA83F6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_35226E2C5FC8567AB67EACF072E071D3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CapitalizedContractCostTable_0ABC0CEE6E76540AA4B6BB2BB74DF55F" xlink:to="loc_srt_RangeAxis_35226E2C5FC8567AB67EACF072E071D3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_A9FAF309F7A1D8F436FA874816356DD2_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_35226E2C5FC8567AB67EACF072E071D3" xlink:to="loc_srt_RangeMember_A9FAF309F7A1D8F436FA874816356DD2_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_98EB108C9EDB5B07B17B93010A083F64" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_35226E2C5FC8567AB67EACF072E071D3" xlink:to="loc_srt_RangeMember_98EB108C9EDB5B07B17B93010A083F64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_96F2010473EC52D295AC580519150548" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_98EB108C9EDB5B07B17B93010A083F64" xlink:to="loc_srt_MinimumMember_96F2010473EC52D295AC580519150548" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_B36A2EBCED0F5C8BB297A8523F759B2D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_98EB108C9EDB5B07B17B93010A083F64" xlink:to="loc_srt_MaximumMember_B36A2EBCED0F5C8BB297A8523F759B2D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalizedContractCostAxis" xlink:label="loc_us-gaap_CapitalizedContractCostAxis_926440F5B67156799FAC6B50DD4547F5" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_CapitalizedContractCostTable_0ABC0CEE6E76540AA4B6BB2BB74DF55F" xlink:to="loc_us-gaap_CapitalizedContractCostAxis_926440F5B67156799FAC6B50DD4547F5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalizedContractCostDomain" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_3CAF44ACBC388FC39EB987481651FCFC_6862C73169D25C1BBA93965D2E71DA81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_926440F5B67156799FAC6B50DD4547F5" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_3CAF44ACBC388FC39EB987481651FCFC_6862C73169D25C1BBA93965D2E71DA81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalizedContractCostDomain" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_71FE0CE754D2593AA4F767B77F64347F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_926440F5B67156799FAC6B50DD4547F5" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_71FE0CE754D2593AA4F767B77F64347F" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_SalesCommissionMember" xlink:label="loc_uis_SalesCommissionMember_78C955E4A91E59EAA2D895CC696E1C33" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_71FE0CE754D2593AA4F767B77F64347F" xlink:to="loc_uis_SalesCommissionMember_78C955E4A91E59EAA2D895CC696E1C33" xlink:type="arc" />
    <link:loc xlink:href="uis-20180930.xsd#uis_RevenuefromContractWithCustomerPaymentPeriod" xlink:label="loc_uis_RevenuefromContractWithCustomerPaymentPeriod_26D93A8D270F597A841FCAFD8EAAEB30" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_172A82ABF01D507AB9EB533C4CD86C02" xlink:to="loc_uis_RevenuefromContractWithCustomerPaymentPeriod_26D93A8D270F597A841FCAFD8EAAEB30" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalizedContractCostGross" xlink:label="loc_us-gaap_CapitalizedContractCostGross_9A2126810484595A835829B3C1FB52EC" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_172A82ABF01D507AB9EB533C4CD86C02" xlink:to="loc_us-gaap_CapitalizedContractCostGross_9A2126810484595A835829B3C1FB52EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CapitalizedContractCostAmortization" xlink:label="loc_us-gaap_CapitalizedContractCostAmortization_D92ED8822C2454BCAB367F23D204CBEC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostLineItems_172A82ABF01D507AB9EB533C4CD86C02" xlink:to="loc_us-gaap_CapitalizedContractCostAmortization_D92ED8822C2454BCAB367F23D204CBEC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_FC48A28CAC29585389F55B7F9E658953" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_4D16F8151AD15391A1F3C5B20A407338" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_FC48A28CAC29585389F55B7F9E658953" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_4D16F8151AD15391A1F3C5B20A407338" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_9288B979BF43563C8AADC32053C3F110" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable_4D16F8151AD15391A1F3C5B20A407338" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_9288B979BF43563C8AADC32053C3F110" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_4D4BE2D93B915BCEA2DEFCDE26F4D7A9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_FC48A28CAC29585389F55B7F9E658953" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_4D4BE2D93B915BCEA2DEFCDE26F4D7A9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_27FAB2221F8D58B09DB42860F544316D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems_FC48A28CAC29585389F55B7F9E658953" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_27FAB2221F8D58B09DB42860F544316D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.unisys.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/SupplementalCashFlowInformation" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/SupplementalCashFlowInformationReconciliationOfCashCashEquivalentsAndRestrictedCashDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/SupplementalCashFlowInformationScheduleOfSupplementalCashFlowInformationDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.unisys.com/role/SupplementalCashFlowInformationTables" xlink:type="extended" />
</link:linkbase>