-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 Mg4wKUopDczQuocU7pPn0UZ20IFud22ec51ks6AF5Fr1ZP7CwLXGcWjRz3WAtmYv
 0ke7qdjrSbtuNNooKQ1OVQ==

<SEC-DOCUMENT>0001279795-05-000006.txt : 20050415
<SEC-HEADER>0001279795-05-000006.hdr.sgml : 20050415
<ACCEPTANCE-DATETIME>20050415180815
ACCESSION NUMBER:		0001279795-05-000006
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050415
FILED AS OF DATE:		20050415
DATE AS OF CHANGE:		20050415

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MURPHY DAVID JAMES III
		CENTRAL INDEX KEY:			0001279795

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-22350
		FILM NUMBER:		05755122

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		650-603-5200

	MAIL ADDRESS:	
		STREET 1:		C/O MERCURY INTERACTIVE CORP
		STREET 2:		379 N. WHISMAN ROAD
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94043
</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>2005-04-15</periodOfReport>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001279795</rptOwnerCik>
            <rptOwnerName>MURPHY DAVID JAMES III</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, Corporate Development</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>29.65</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-04-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>43.17</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>29.65</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-04-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2003-12-31</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2012-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>150000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">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="F2">This sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Susan J. Skaer, attorney-in-fact for David James Murphy III</signatureName>
        <signatureDate>2005-04-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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