-----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,
 M/V8o85LHFe3b1anH3Ntr5Wl86O9Q5jNEWcHAD3Aw/3gcHi+SubQy+6hAiWkhRCf
 grlKBkzs/3ml0iMVY9TzxA==

<SEC-DOCUMENT>0001181431-03-013624.txt : 20030710
<SEC-HEADER>0001181431-03-013624.hdr.sgml : 20030710
<ACCEPTANCE-DATETIME>20030710150116
ACCESSION NUMBER:		0001181431-03-013624
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030710
FILED AS OF DATE:		20030710

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HALL CHARLES L
		CENTRAL INDEX KEY:			0001220742

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10145
		FILM NUMBER:		03781815

	BUSINESS ADDRESS:	
		STREET 1:		1221 MCKINNEY ST.,
		STREET 2:		SUITE 700
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77010
		BUSINESS PHONE:		7136527280

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LYONDELL CHEMICAL CO
		CENTRAL INDEX KEY:			0000842635
		STANDARD INDUSTRIAL CLASSIFICATION:	INDUSTRIAL ORGANIC CHEMICALS [2860]
		IRS NUMBER:				954160558
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1221 MCKINNEY ST
		STREET 2:		STE 700
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77010
		BUSINESS PHONE:		7136527200

	MAIL ADDRESS:	
		STREET 1:		1221 MCKINNEY ST
		STREET 2:		SUITE 700
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77010

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LYONDELL PETROCHEMICAL CO
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd13028.xml
<DESCRIPTION>SPECIAL RESTRICTED STOCK GRANT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>
    <schemaVersion>X0101</schemaVersion>

    <documentType>4</documentType>
<periodOfReport>2003-07-10</periodOfReport>
<notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000842635</issuerCik>
        <issuerName>LYONDELL CHEMICAL CO</issuerName>
        <issuerTradingSymbol>lyo</issuerTradingSymbol></issuer>
<reportingOwner>
<reportingOwnerId>
            <rptOwnerCik>0001220742</rptOwnerCik>
            <rptOwnerName>HALL CHARLES L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
<isDirector>0</isDirector>
<isOfficer>1</isOfficer>
<isTenPercentOwner>0</isTenPercentOwner>
<isOther>0</isOther>
<officerTitle>Vice President and Controller</officerTitle>
<otherText></otherText></reportingOwnerRelationship></reportingOwner>
<nonDerivativeSecurity>
<securityTitle>
<value>Common Stock</value></securityTitle>
<transactionDate>
<value>2003-07-10</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionTimeliness>
<value></value></transactionTimeliness>
<transactionAmounts>
<transactionShares>
<value>11000</value></transactionShares>
<transactionValue>
<value>0.00</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>14669</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></nonDerivativeSecurity>
<derivativeSecurity>
<securityTitle>
<value>Phantom Stock</value></securityTitle>
<conversionOrExercisePrice>
<value>0</value>
<footnoteId id="F1"/></conversionOrExercisePrice>
<transactionDate>
<value>2003-07-10</value></transactionDate>
<transactionCoding>
<transactionFormType>4</transactionFormType>
<transactionCode>A</transactionCode>
<equitySwapInvolved>0</equitySwapInvolved></transactionCoding>
<transactionAmounts>
<transactionShares>
<value>11000</value></transactionShares>
<transactionValue>
<value>0</value></transactionValue>
<transactionAcquiredDisposedCode>
<value>A</value></transactionAcquiredDisposedCode></transactionAmounts>
<exerciseDate>
<value>2006-07-10</value>
<footnoteId id="F2"/></exerciseDate>
<expirationDate>
<value>2008-07-10</value></expirationDate>
<underlyingSecurity>
<underlyingSecurityTitle>
<value>Common Stock</value></underlyingSecurityTitle>
<underlyingSecurityShares>
<value>11000</value></underlyingSecurityShares></underlyingSecurity>
<postTransactionAmounts>
<sharesOwnedFollowingTransaction>
<value>11000</value></sharesOwnedFollowingTransaction></postTransactionAmounts>
<ownershipNature>
<directOrIndirectOwnership>
<value>D</value></directOrIndirectOwnership>
<natureOfOwnership>
<value></value></natureOfOwnership></ownershipNature></derivativeSecurity>
<footnotes>
<footnote id="F1">The phantom stock converts to common stock on a one-for-one basis.</footnote>
<footnote id="F2">The award vests over five-years beginning three years from the date of grant with 60% vesting on July 10, 2006, 20% vesting on July 10, 2007 and 20% vesting July 10, 2008.</footnote></footnotes>
<ownerSignature>
<signatureName>KERRY A. GALVIN, as attorney-in-fact for Charles Hall</signatureName>
<signatureDate>2003-07-10</signatureDate></ownerSignature></ownershipDocument>


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