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Proc-Type: 2001,MIC-CLEAR
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<SEC-DOCUMENT>0001311761-08-000035.txt : 20080528
<SEC-HEADER>0001311761-08-000035.hdr.sgml : 20080528
<ACCEPTANCE-DATETIME>20080528132658
ACCESSION NUMBER:		0001311761-08-000035
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080527
FILED AS OF DATE:		20080528
DATE AS OF CHANGE:		20080528

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KILROY REALTY CORP
		CENTRAL INDEX KEY:			0001025996
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				954598246
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		12200 W. OLYMPIC BLVD., SUITE 200
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90064
		BUSINESS PHONE:		3104818400

	MAIL ADDRESS:	
		STREET 1:		12200 W. OLYMPIC BLVD., SUITE 200
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90064

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KILROY JOHN B JR
		CENTRAL INDEX KEY:			0001214277

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12675
		FILM NUMBER:		08863014

	MAIL ADDRESS:	
		STREET 1:		12200 W OLYMPIC BLVD
		STREET 2:		SUITE 200
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90064
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-05-27</periodOfReport>

    <issuer>
        <issuerCik>0001025996</issuerCik>
        <issuerName>KILROY REALTY CORP</issuerName>
        <issuerTradingSymbol>NYSE: KRC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001214277</rptOwnerCik>
            <rptOwnerName>KILROY JOHN B JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>12200 W. OLYMPIC BOULEVARD</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 200</rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90064</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

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            <transactionAmounts>
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                <transactionPricePerShare>
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                <transactionAcquiredDisposedCode>
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                <transactionShares>
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                <transactionPricePerShare>
                    <value>52.39</value>
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                <transactionAcquiredDisposedCode>
                    <value>D</value>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>400</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>52.41</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>303050</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Tyler H. Rose, as attorney-in-fact for John B. Kilroy, Jr.</signatureName>
        <signatureDate>2008-05-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----