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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 PA0P5Slw/pf1Wt2sawkF8X7uGjkGmJWsRjBVaDLU5GBnWF+Qpgxfuqyqn8uDLclB
 QROgfRZ0S3Xlrh4hX/d7kg==

<SEC-DOCUMENT>0000716039-03-000055.txt : 20030702
<SEC-HEADER>0000716039-03-000055.hdr.sgml : 20030702
<ACCEPTANCE-DATETIME>20030702150911
ACCESSION NUMBER:		0000716039-03-000055
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030701
FILED AS OF DATE:		20030702

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HERRINGER FRANK C
		CENTRAL INDEX KEY:			0001171694

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08483
		FILM NUMBER:		03771551

	BUSINESS ADDRESS:	
		STREET 1:		TRANSAMERICA CORP
		STREET 2:		600 MONTGOMERY ST 16TH FL
		CITY:			SAN FRANCISCO
		STATE:			CA
		ZIP:			94111

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNOCAL CORP
		CENTRAL INDEX KEY:			0000716039
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				953825062
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		2141 ROSECRANS AVE
		STREET 2:		STE 4000
		CITY:			EL SEGUNDO
		STATE:			CA
		ZIP:			90245
		BUSINESS PHONE:		3107267600

	MAIL ADDRESS:	
		STREET 1:		2141 ROSECRANS AVE
		STREET 2:		STE 4000
		CITY:			EL SEGUNDO
		STATE:			CA
		ZIP:			90245
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>f4forherr.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0101</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-07-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000716039</issuerCik>
        <issuerName>UNOCAL CORP</issuerName>
        <issuerTradingSymbol>UCL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001171694</rptOwnerCik>
            <rptOwnerName>HERRINGER FRANK C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeSecurity>
        <securityTitle>
            <value>Common Stock $1.00 Par Value</value>
            <footnoteId id="F1"/>
        </securityTitle>
        <transactionDate>
            <value>2003-07-01</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>A</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
            <footnoteId id="F2"/>
        </transactionCoding>
        <transactionAmounts>
            <transactionShares>
                <value>413.3242</value>
            </transactionShares>
            <transactionValue>
                <value>29.7587</value>
                <footnoteId id="F3"/>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>A</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <postTransactionAmounts>
            <sharesOwnedFollowingTransaction>
                <value>20524.2098</value>
                <footnoteId id="F4"/>
            </sharesOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </nonDerivativeSecurity>

    <footnotes>
        <footnote id="F1">Common Stock has attached Preferred Stock Purchase Rights.
If and when the Rights become exercisable, the holders
would initially be entitled to purchase one one-hundredth
of a share of Series B Junior Participating Preferred stock
at a purchase price determined pursuant to the Rights
Agreement.</footnote>
        <footnote id="F2">Deferred compensation under the 2001 Directors'
Deferred Compensation and Stock Award Plan.  Each unit is
payable in one share of Common Stock at the end of the
deferral periods.</footnote>
        <footnote id="F3">The price used to determine the number of Stock Units to be
credited is the average price of Unocal Corporation Common
Stock during the period in which the deferred compensation
is earned.</footnote>
        <footnote id="F4">In addition Custodian for a Minor owns 400 shares and Family Trust owns 51,332 shares.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Paul R. Moore, Attorney-In-Fact</signatureName>
        <signatureDate>2003-07-02</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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