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  <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_OutsideDirectorsMember" abstract="true" name="OutsideDirectorsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_DebtPaymentsRefinancedDebtMember" abstract="true" name="DebtPaymentsRefinancedDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_CostReimbursementAndFixedPriceIncentiveFeeMember" abstract="true" name="CostReimbursementAndFixedPriceIncentiveFeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_NotesWhichMatureOnDecemberTwoThousandTwentyMember" abstract="true" name="NotesWhichMatureOnDecemberTwoThousandTwentyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_DefenseSolutionSegmentMember" abstract="true" name="DefenseSolutionSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_InterestRateSwapMaturityDateAugustTwentyTwentyFiveMember" abstract="true" name="InterestRateSwapMaturityDateAugustTwentyTwentyFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_CommercialCybersecurityBusinessMember" abstract="true" name="CommercialCybersecurityBusinessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_SaleLeasebackTransactionTaxImpact" abstract="false" name="SaleLeasebackTransactionTaxImpact" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_AcquisitionIntegrationAndRestructuringCosts" abstract="false" name="AcquisitionIntegrationAndRestructuringCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_LossContingencyPercentageofDamagesCoveredBetweenThirtyEightMillionandSixtyFourMillionSettlementAmount" abstract="false" name="LossContingencyPercentageofDamagesCoveredBetweenThirtyEightMillionandSixtyFourMillionSettlementAmount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_ScheduleOfCertainFinancialStatementCaptionsTableTextBlock" abstract="false" name="ScheduleOfCertainFinancialStatementCaptionsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="ldos_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsWriteOff" abstract="false" name="DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsWriteOff" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_CivilSegmentMember" abstract="true" name="CivilSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_InterestExpenseNetAbstract" abstract="true" name="InterestExpenseNetAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_SummaryofIncomeTaxRelatedBalanceonBalanceSheetTableTextBlock" abstract="false" name="SummaryofIncomeTaxRelatedBalanceonBalanceSheetTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <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_FinanceLeaseCost" abstract="false" name="FinanceLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_NotesWhichMatureOnDecemberTwoThousandFortyMember" abstract="true" name="NotesWhichMatureOnDecemberTwoThousandFortyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_ShareBasedCompensationArrangementByShareBasedPaymentAwardCyclePerformancePeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardCyclePerformancePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="ldos_IMXMember" abstract="true" name="IMXMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_NoncurrentLeaseLiabilitiesAbstract" abstract="true" name="NoncurrentLeaseLiabilitiesAbstract" 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="dtr-types:textBlockItemType"/>
  <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_HealthStaffAugmentationBusinessMember" abstract="true" name="HealthStaffAugmentationBusinessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_GibbsCoxIncMember" abstract="true" name="GibbsCoxIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_LockheedMartinMember" abstract="true" name="LockheedMartinMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_EffectiveIncomeTaxRateReconciliationStockBasisinSubsidiaryHeldforSale" abstract="false" name="EffectiveIncomeTaxRateReconciliationStockBasisinSubsidiaryHeldforSale" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_DeferredTaxAssetsOperatingLeaseLiabilities" abstract="false" name="DeferredTaxAssetsOperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_TwoThousandSixandTwentySeventeenEquityIncentivePlansMember" abstract="true" name="TwoThousandSixandTwentySeventeenEquityIncentivePlansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_DisposalGroupIncludingDiscontinuedOperationAssetsDivested" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationAssetsDivested" nillable="true" xbrli:periodType="instant" 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="dtr-types: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_TermLoanDueMayTwentyTwentyTwoMember" abstract="true" name="TermLoanDueMayTwentyTwentyTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_OtherGovernmentAgenciesMember" abstract="true" name="OtherGovernmentAgenciesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_DisposalGroupIncludingDiscontinuedOperationTransactionRelatedCosts" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationTransactionRelatedCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_DeferredTaxLiabilityTaxDeferredExpensesCompensationAndBenefitsEmployeeBenefitContributions" abstract="false" name="DeferredTaxLiabilityTaxDeferredExpensesCompensationAndBenefitsEmployeeBenefitContributions" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_GibbsAndCoxMember" abstract="true" name="GibbsAndCoxMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_CashpaidforamountsincludedinmeasurementofleaseliabilitiesAbstract" abstract="true" name="CashpaidforamountsincludedinmeasurementofleaseliabilitiesAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_GuaranteedObligation" abstract="false" name="GuaranteedObligation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_SDABusinessesMember" abstract="true" name="SDABusinessesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_LeaseliabilitiesarisingfromobtainingROUassetsAbstract" abstract="true" name="LeaseliabilitiesarisingfromobtainingROUassetsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_WeightedaveragediscountrateAbstract" abstract="true" name="WeightedaveragediscountrateAbstract" 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_DebtInstrumentCovenantAdjustedConsolidatedTotalDebtToConsolidatedEBITDARatioFollowingMaterialAcquisition" abstract="false" name="DebtInstrumentCovenantAdjustedConsolidatedTotalDebtToConsolidatedEBITDARatioFollowingMaterialAcquisition" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="ldos_SecurityProductsMember" abstract="true" name="SecurityProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types: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_GoodwillReAllocations" abstract="false" name="GoodwillReAllocations" nillable="true" xbrli:periodType="duration" 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_AviationMissileSolutionsLLCMember" abstract="true" name="AviationMissileSolutionsLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_UkPlanMember" abstract="true" name="UkPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_USGovernmentMember" abstract="true" name="USGovernmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_TheCreditAgreementMember" abstract="true" name="TheCreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_TermLoanDueJanuaryTwentyTwentyFiveMember" abstract="true" name="TermLoanDueJanuaryTwentyTwentyFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_NumberofDeferredCompensationPlans" abstract="false" name="NumberofDeferredCompensationPlans" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_TimeAndMaterialsAndFixedPriceLevelOfEffortMember" abstract="true" name="TimeAndMaterialsAndFixedPriceLevelOfEffortMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ldos_VirnetXIncMember" abstract="true" name="VirnetXIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_TaxCreditCarryforwardExpectedToUtilize" abstract="false" name="TaxCreditCarryforwardExpectedToUtilize" 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_OperatingLeaseRightofUseAssetLeaseExpense" abstract="false" name="OperatingLeaseRightofUseAssetLeaseExpense" 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_DecreaseInIncomeBeforeIncomeTaxesFromChangesInContractEstimates" abstract="false" name="DecreaseInIncomeBeforeIncomeTaxesFromChangesInContractEstimates" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ldos_PropertyPlantAndAdditionsNonCashInvestingActivity" abstract="false" name="PropertyPlantAndAdditionsNonCashInvestingActivity" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_NumberOfInfringedPatents" abstract="false" name="NumberOfInfringedPatents" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="ldos_DisclosureScheduleOfCertainFinancialStatementCaptionsAbstract" abstract="true" name="DisclosureScheduleOfCertainFinancialStatementCaptionsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="ldos_ChangesInEstimatesOnContractsPolicyTextBlock" abstract="false" name="ChangesInEstimatesOnContractsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
</xs:schema>
