-----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,
 O3wg2KzyxBieziV9MEyFqqb1Eh2IPNLKJzBCz8SLf52W8nc3Jb0tVD1yVB4c8ha8
 ZqR5n65uRSbXkj2O+WIpjQ==

<SEC-DOCUMENT>0001179110-06-006948.txt : 20060322
<SEC-HEADER>0001179110-06-006948.hdr.sgml : 20060322
<ACCEPTANCE-DATETIME>20060322160005
ACCESSION NUMBER:		0001179110-06-006948
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060320
FILED AS OF DATE:		20060322
DATE AS OF CHANGE:		20060322

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROBINSON RICHARD B
		CENTRAL INDEX KEY:			0001228357

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10389
		FILM NUMBER:		06703820

	BUSINESS ADDRESS:	
		STREET 1:		C/O WESTERN GAS RESOURCES INC
		STREET 2:		1099 18TH STREET STE 1200
		CITY:			DENVER
		STATE:			CO
		ZIP:			80202
		BUSINESS PHONE:		3034525603

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WESTERN GAS RESOURCES INC
		CENTRAL INDEX KEY:			0000856716
		STANDARD INDUSTRIAL CLASSIFICATION:	NATURAL GAS DISTRIBUTION [4924]
		IRS NUMBER:				841127613
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1099 18TH STREET, SUITE 1200
		CITY:			DENVER
		STATE:			CO
		ZIP:			80202-1955
		BUSINESS PHONE:		303 452 5603

	MAIL ADDRESS:	
		STREET 1:		1099 18TH STREET, SUITE 1200
		CITY:			DENVER
		STATE:			CO
		ZIP:			80202-1955
</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>2006-03-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000856716</issuerCik>
        <issuerName>WESTERN GAS RESOURCES INC</issuerName>
        <issuerTradingSymbol>WGR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001228357</rptOwnerCik>
            <rptOwnerName>ROBINSON RICHARD B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1099 18TH STREET, SUITE 1200</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>DENVER</rptOwnerCity>
            <rptOwnerState>CO</rptOwnerState>
            <rptOwnerZipCode>80202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-03-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>45.34</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17950</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2006-03-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3350</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17950</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">9,000 shares held by the Robinson &amp; Diss pension fund for the benefit of the Reporting Person, 1,200 shares held jointly by the Reporting Person and his spouse as trustees for their children, 400 shares held indirectly though Reporting Person's interests in a family-owned corporation, 6,700 shares held by Reporting Person's spouse, and 650 held directly by the Reporting Person.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ William J. Krysiak as Attorney-in-Fact for Richard B. Robinson</signatureName>
        <signatureDate>2006-03-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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