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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,
 O2xNv4m1m5KGVmlqIfycK27k/l6j6lkm5nZZ+PrBcKvuEVFQ6hwHq1+s+wbOMuHd
 fYd6lWSPos0PAK5WtdIsFA==

<SEC-DOCUMENT>0001179110-04-017544.txt : 20040902
<SEC-HEADER>0001179110-04-017544.hdr.sgml : 20040902
<ACCEPTANCE-DATETIME>20040902170516
ACCESSION NUMBER:		0001179110-04-017544
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040831
FILED AS OF DATE:		20040902
DATE AS OF CHANGE:		20040902

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HEPPERMANN DONALD C
		CENTRAL INDEX KEY:			0001235073

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14841
		FILM NUMBER:		041014516

	BUSINESS ADDRESS:	
		STREET 1:		155 INVERNESS DRIVE
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112-5004

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MARKWEST HYDROCARBON INC
		CENTRAL INDEX KEY:			0001019756
		STANDARD INDUSTRIAL CLASSIFICATION:	CRUDE PETROLEUM & NATURAL GAS [1311]
		IRS NUMBER:				841352233
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		155 INVERNESS DRIVE WEST
		STREET 2:		SUITE 200
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112-5004
		BUSINESS PHONE:		3032908700

	MAIL ADDRESS:	
		STREET 1:		155 INVERNESS DRIVE WEST
		STREET 2:		SUITE 200
		CITY:			ENGLEWOOD
		STATE:			CO
		ZIP:			80112-5004
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-08-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001019756</issuerCik>
        <issuerName>MARKWEST HYDROCARBON INC</issuerName>
        <issuerTradingSymbol>MWP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001235073</rptOwnerCik>
            <rptOwnerName>HEPPERMANN DONALD C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O MARKWEST HYDROCARBON, INC</rptOwnerStreet1>
            <rptOwnerStreet2>155 INVERNESS DRIVE WEST, STE 200</rptOwnerStreet2>
            <rptOwnerCity>ENGLEWOOD</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80112</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>12.75</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-08-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2007-08-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The stock option fully vests on the first anniversary date of the grant date, which grant date is three years prior to the reported expiration date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Andy Schulz POA for Donald C Heppermann</signatureName>
        <signatureDate>2004-09-02</signatureDate>
    </ownerSignature>
</ownershipDocument>

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