-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 JZpF6vz+fNoxAWvdgMQ9dt9Sl5xZOL1lKbebsi3C9FTHjV6IP6UqUM650lp1gVL0
 ruy06tb7M0Zi1dWSBWnijg==

<SEC-DOCUMENT>0001204303-05-000001.txt : 20050207
<SEC-HEADER>0001204303-05-000001.hdr.sgml : 20050207
<ACCEPTANCE-DATETIME>20050207122129
ACCESSION NUMBER:		0001204303-05-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050203
FILED AS OF DATE:		20050207
DATE AS OF CHANGE:		20050207

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SCARLAT YUVAL
		CENTRAL INDEX KEY:			0001204303

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22350
		FILM NUMBER:		05579620

	BUSINESS ADDRESS:	
		STREET 1:		C/O MERCURY INTERACTIVE CORPORATION
		STREET 2:		1325 BORREGAS AVENUE
		CITY:			SUNNYVALE
		STATE:			CA
		ZIP:			94089
		BUSINESS PHONE:		4088225200

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MERCURY INTERACTIVE CORP
		CENTRAL INDEX KEY:			0000867058
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				770224776
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		379 N. WHISMAN ROAD
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94043-3969
		BUSINESS PHONE:		6506035300

	MAIL ADDRESS:	
		STREET 1:		379 N. WHISMAN ROAD
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94043-3969

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MERCURY INTERACTIVE CORPORATION
		DATE OF NAME CHANGE:	19930910
</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>2005-02-03</periodOfReport>

    <issuer>
        <issuerCik>0000867058</issuerCik>
        <issuerName>MERCURY INTERACTIVE CORP</issuerName>
        <issuerTradingSymbol>MERQ</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001204303</rptOwnerCik>
            <rptOwnerName>SCARLAT YUVAL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>MERCURY INTERACTIVE CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>379 N. WHISMAN ROAD</rptOwnerStreet2>
            <rptOwnerCity>MOUNTAIN VIEW</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94043</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. VP, Products</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>47</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2670</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Valentin Yuval Scarlat &amp; Smadar Scarlat TTEES of the Scarlat Trust created 2/16/00</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>48.94</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-02-03</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>25000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2006-02-03</value>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-02-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>25000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>390000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Includes 988 shares of common stock acquired on 2/15/04 pursuant to the Company's employee stock purchase plan.</footnote>
        <footnote id="F2">25% of the total number of shares subject to the option vest one year from the vesting commencement date and the remaining 75% vest on a monthly basis over the next 36 months.  The option is immediately exercisable for all shares subject to the option, including those that have not yet vested, however, unvested shares purchased through option exercises are subject to the issuer's right of repurchase upon the termination of employment.</footnote>
        <footnote id="F3">Includes 47 shares of common stock acquired on 8/15/04 pursuant to the Company's employee stock purchase plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Susan J. Skaer, Attorney-in-fact for Yuval Scarlat</signatureName>
        <signatureDate>2005-02-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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