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  <xs:element id="ldos_WeightedaveragediscountrateAbstract" abstract="true" name="WeightedaveragediscountrateAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_FinanceLeaseCost" abstract="false" name="FinanceLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnDecemberTwoThousandTwentyMember" abstract="true" name="NotesWhichMatureOnDecemberTwoThousandTwentyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_SDABusinessesMember" abstract="true" name="SDABusinessesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightOfUseAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_PaymentOfTaxIndemnificationLiability" abstract="false" name="PaymentOfTaxIndemnificationLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_CompositionOfCertainFinancialStatementCaptionsTextBlock" abstract="false" name="CompositionOfCertainFinancialStatementCaptionsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="ldos_ShareBasedPaymentArrangementTrancheFourMember" abstract="true" name="ShareBasedPaymentArrangementTrancheFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedPayrollAndEmployeeBenefits" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAccruedPayrollAndEmployeeBenefits" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TwoThousandSixandTwentySeventeenEquityIncentivePlansMember" abstract="true" name="TwoThousandSixandTwentySeventeenEquityIncentivePlansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_LeaseLiabilityNoncurrent" abstract="false" name="LeaseLiabilityNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_AccountsReceivableCreditLossExpenseAndRecoveriesNet" abstract="false" name="AccountsReceivableCreditLossExpenseAndRecoveriesNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_GaithersburgMarylandMember" abstract="true" name="GaithersburgMarylandMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnMayTwoThousandThirtyMember" abstract="true" name="NotesWhichMatureOnMayTwoThousandThirtyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_OtherCommitmentsAndContingenciesLineItems" abstract="true" name="OtherCommitmentsAndContingenciesLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_GuaranteedObligationFiscalYearMaturityTableTextBlock" abstract="false" name="GuaranteedObligationFiscalYearMaturityTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="ldos_PrepaidTaxesandTaxRefundReceivable" abstract="false" name="PrepaidTaxesandTaxRefundReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_AcceleratedShareRepurchaseMember" abstract="true" name="AcceleratedShareRepurchaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_LockheedMartinMember" abstract="true" name="LockheedMartinMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_NoncurrentRightofUseAssetsAbstract" abstract="true" name="NoncurrentRightofUseAssetsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_EffectiveIncomeTaxRateReconciliationTaxableConversionofSubsidiary" abstract="false" name="EffectiveIncomeTaxRateReconciliationTaxableConversionofSubsidiary" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnJulyTwoThousandThirtyTwoMember" abstract="true" name="NotesWhichMatureOnJulyTwoThousandThirtyTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnMayTwoThousandTwentyFiveMember" abstract="true" name="NotesWhichMatureOnMayTwoThousandTwentyFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_NotesPayableAndFinanceLeasesDueOnVariousDatesThroughFiscalTwoThousandThirtyMember" abstract="true" name="NotesPayableAndFinanceLeasesDueOnVariousDatesThroughFiscalTwoThousandThirtyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_ChangeInUnrealizedGainLossOnHedgedItemInCashFlowHedge" abstract="false" name="ChangeInUnrealizedGainLossOnHedgedItemInCashFlowHedge" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TermLoanADollarThreeHundredandTenMillionDueAugustTwentyTwentyThreeMember" abstract="true" name="TermLoanADollarThreeHundredandTenMillionDueAugustTwentyTwentyThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_EffectiveIncomeTaxRateReconciliationImpactOfForeignOperations" abstract="false" name="EffectiveIncomeTaxRateReconciliationImpactOfForeignOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_InformationSystemsGlobalSolutionsBusinessofLockheedMartinMember" abstract="true" name="InformationSystemsGlobalSolutionsBusinessofLockheedMartinMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_DebtInstrumentBasisSpreadOnVariableRateIncreaseDecrease" abstract="false" name="DebtInstrumentBasisSpreadOnVariableRateIncreaseDecrease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="ldos_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAndAccruedLiabilities" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAndAccruedLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_BusinessCombinationWorkingCapitalNet" abstract="false" name="BusinessCombinationWorkingCapitalNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LineOfCreditFacilityDurationFeePercentage" abstract="false" name="LineOfCreditFacilityDurationFeePercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="ldos_CashpaidforamountsincludedinmeasurementofleaseliabilitiesAbstract" abstract="true" name="CashpaidforamountsincludedinmeasurementofleaseliabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_DelayedDrawTermLoanFacilityMember" abstract="true" name="DelayedDrawTermLoanFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_CommercialCybersecurityBusinessMember" abstract="true" name="CommercialCybersecurityBusinessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_LossContingencyPercentageofDamagesCoveredBetweenThirtyEightMillionandSixtyFourMillionSettlementAmount" abstract="false" name="LossContingencyPercentageofDamagesCoveredBetweenThirtyEightMillionandSixtyFourMillionSettlementAmount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="ldos_TransitionCostsandProjectAssetsNetNoncurrent" abstract="false" name="TransitionCostsandProjectAssetsNetNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LeaseRightOfUseAsset" abstract="false" name="LeaseRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_OtherGovernmentAgenciesMember" abstract="true" name="OtherGovernmentAgenciesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_ChangesInEstimatesOnContractsPolicyTextBlock" abstract="false" name="ChangesInEstimatesOnContractsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="ldos_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisSettlements" abstract="false" name="FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisSettlements" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DeferredTaxAssetsTaxCreditAndNetOperatingLossCarryforwards" abstract="false" name="DeferredTaxAssetsTaxCreditAndNetOperatingLossCarryforwards" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LiabilityForUncertainTaxPositions" abstract="false" name="LiabilityForUncertainTaxPositions" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TermLoanDueJanuaryTwentyTwentyFiveMember" abstract="true" name="TermLoanDueJanuaryTwentyTwentyFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_NumberOfReportableSegmentsGoodwillReallocation" abstract="false" name="NumberOfReportableSegmentsGoodwillReallocation" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_MissionSupportAllianceMember" abstract="true" name="MissionSupportAllianceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_ProceedsFromSaleOfReceivablesOperatingActivities" abstract="false" name="ProceedsFromSaleOfReceivablesOperatingActivities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DecreaseInIncomeBeforeIncomeTaxesFromChangesInContractEstimates" abstract="false" name="DecreaseInIncomeBeforeIncomeTaxesFromChangesInContractEstimates" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_SuretyBondsOutstandingNotionalAmount" abstract="false" name="SuretyBondsOutstandingNotionalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DebtInstrumentDebtAgreementInterestRateIncreaseUponFailure" abstract="false" name="DebtInstrumentDebtAgreementInterestRateIncreaseUponFailure" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="ldos_OperatingLossCarryforwardsExpectedToUtilize" abstract="false" name="OperatingLossCarryforwardsExpectedToUtilize" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LitigationSettlementAmountPercentageofTotal" abstract="false" name="LitigationSettlementAmountPercentageofTotal" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="ldos_MissionSupportAllianceLLCMember" abstract="true" name="MissionSupportAllianceLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_OperatingCyclePolicyPolicyTextBlock" abstract="false" name="OperatingCyclePolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="ldos_CurrentLeaseLiabilitiesAbstract" abstract="true" name="CurrentLeaseLiabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnFebruaryTwoThousandThirtyOneMember" abstract="true" name="NotesWhichMatureOnFebruaryTwoThousandThirtyOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_GoodwillReAllocations" abstract="false" name="GoodwillReAllocations" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NumberofDeferredCompensationPlans" abstract="false" name="NumberofDeferredCompensationPlans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_LeaseliabilitiesarisingfromobtainingROUassetsAbstract" abstract="true" name="LeaseliabilitiesarisingfromobtainingROUassetsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_LitigationSettlementAmountAwardedfromOtherPartyRoyaltyRatePerDevice" abstract="false" name="LitigationSettlementAmountAwardedfromOtherPartyRoyaltyRatePerDevice" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityYearTwo" abstract="false" name="GuaranteedObligationMaturityYearTwo" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DyneticsMember" abstract="true" name="DyneticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_OtherIncomeExpenseNet" abstract="false" name="OtherIncomeExpenseNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_IncreaseDecreaseInIncomeFromChangeInContractEstimates" abstract="false" name="IncreaseDecreaseInIncomeFromChangeInContractEstimates" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TransitionCostsandProjectAssetsNetCurrent" abstract="false" name="TransitionCostsandProjectAssetsNetCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_AggregateIntrinsicValueAbstract" abstract="true" name="AggregateIntrinsicValueAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityYearFive" abstract="false" name="GuaranteedObligationMaturityYearFive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_ScheduleOfCertainFinancialStatementCaptionsTextBlock" abstract="false" name="ScheduleOfCertainFinancialStatementCaptionsTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="ldos_BusinessAcquisitionProFormaNetIncomeLossAttributableToParent" abstract="false" name="BusinessAcquisitionProFormaNetIncomeLossAttributableToParent" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_InterestExpenseNetAbstract" abstract="true" name="InterestExpenseNetAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_DebtInstrumentNumberOfOptionsToExtendTerm" abstract="false" name="DebtInstrumentNumberOfOptionsToExtendTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_LossContingencyPercentageofDamagesCoveredExcessofSixtyFourMillionSettlementAmount" abstract="false" name="LossContingencyPercentageofDamagesCoveredExcessofSixtyFourMillionSettlementAmount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityYearOne" abstract="false" name="GuaranteedObligationMaturityYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LitigationSettlementAwardedfromtheOtherPartyInterestandLegalFees" abstract="false" name="LitigationSettlementAwardedfromtheOtherPartyInterestandLegalFees" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_IncreaseDecreaseInAccountsPayableAndAccruedLiabilitiesAndOtherNoncurrentLiabilities" abstract="false" name="IncreaseDecreaseInAccountsPayableAndAccruedLiabilitiesAndOtherNoncurrentLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_PrepaidContractCosts" abstract="false" name="PrepaidContractCosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnMayTwoThousandTwentyThreeMember" abstract="true" name="NotesWhichMatureOnMayTwoThousandTwentyThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_DeferredTaxLiabilityTaxDeferredExpensesCompensationAndBenefitsEmployeeBenefitContributions" abstract="false" name="DeferredTaxLiabilityTaxDeferredExpensesCompensationAndBenefitsEmployeeBenefitContributions" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_ScheduleOfShareBasedCompensationAndRelatedTaxBenefitsRecognizedTableTableTextBlock" abstract="false" name="ScheduleOfShareBasedCompensationAndRelatedTaxBenefitsRecognizedTableTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="ldos_WeightedaverageremainingleasetermAbstract" abstract="true" name="WeightedaverageremainingleasetermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_USGovernmentMember" abstract="true" name="USGovernmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityYearThree" abstract="false" name="GuaranteedObligationMaturityYearThree" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DeferredTaxAssetsOperatingLeaseLiabilities" abstract="false" name="DeferredTaxAssetsOperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_InterestRateSwapMaturityDateAugustTwentyTwentyFiveMember" abstract="true" name="InterestRateSwapMaturityDateAugustTwentyTwentyFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_RoyaltyRatePercentage" abstract="false" name="RoyaltyRatePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityYearFour" abstract="false" name="GuaranteedObligationMaturityYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_DebtInstrumentCovenantAdjustedConsolidatedTotalDebtToConsolidatedEBITDARatioFollowingMaterialAcquisition" abstract="false" name="DebtInstrumentCovenantAdjustedConsolidatedTotalDebtToConsolidatedEBITDARatioFollowingMaterialAcquisition" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="ldos_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodWeightedAverageGrantDateStockPrice" abstract="false" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsGrantsinPeriodWeightedAverageGrantDateStockPrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:perShareItemType"/>
  <xs:element id="ldos_TaxCreditCarryforwardExpectedToUtilize" abstract="false" name="TaxCreditCarryforwardExpectedToUtilize" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_BusinessCombinationAcquisitionAndIntegrationRelatedCosts" abstract="false" name="BusinessCombinationAcquisitionAndIntegrationRelatedCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_GibbsCoxIncMember" abstract="true" name="GibbsCoxIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_InterestIncomeExpenseNetMember" abstract="true" name="InterestIncomeExpenseNetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_CostReimbursementAndFixedPriceIncentiveFeeMember" abstract="true" name="CostReimbursementAndFixedPriceIncentiveFeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_DefenseSolutionSegmentMember" abstract="true" name="DefenseSolutionSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_DebtInstrumentCovenantConsolidatedTotalDebtToConsolidatedEBITDARatioNumberOfIncreases" abstract="false" name="DebtInstrumentCovenantConsolidatedTotalDebtToConsolidatedEBITDARatioNumberOfIncreases" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_MSAVentureMember" abstract="true" name="MSAVentureMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_GuaranteedObligationMaturityAfterYearFive" abstract="false" name="GuaranteedObligationMaturityAfterYearFive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilities" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_GainContingencyPatentsFoundInfringedNumberOther" abstract="false" name="GainContingencyPatentsFoundInfringedNumberOther" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnJulyTwoThousandThirtyThreeMember" abstract="true" name="NotesWhichMatureOnJulyTwoThousandThirtyThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_ReceivableCollectiblePeriod" abstract="false" name="ReceivableCollectiblePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ldos_VirnetXIncMember" abstract="true" name="VirnetXIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="ldos_LitigationSettlementAmountAwardedfromOtherPartyPreInterest" abstract="false" name="LitigationSettlementAmountAwardedfromOtherPartyPreInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
