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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,
 I7TT5MQTe4hWUWIHgjnVZPiWxEmq5qJeVtgmyhe0NGQEZuO0k4d6uWgBMupnKtaj
 P7ahk/n4Hvm3L3wpNogmbw==

<SEC-DOCUMENT>0001179110-05-002943.txt : 20050210
<SEC-HEADER>0001179110-05-002943.hdr.sgml : 20050210
<ACCEPTANCE-DATETIME>20050210144459
ACCESSION NUMBER:		0001179110-05-002943
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041231
FILED AS OF DATE:		20050210
DATE AS OF CHANGE:		20050210

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KEY ENERGY SERVICES INC
		CENTRAL INDEX KEY:			0000318996
		STANDARD INDUSTRIAL CLASSIFICATION:	DRILLING OIL & GAS WELLS [1381]
		IRS NUMBER:				042648081
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		TOW TOWER CENTER
		STREET 2:		20TH FL
		CITY:			EAST BRUNSWICK
		STATE:			NJ
		ZIP:			08816
		BUSINESS PHONE:		9082474822

	MAIL ADDRESS:	
		STREET 1:		P O BOX 10627
		CITY:			MIDLAND
		STATE:			TX
		ZIP:			79702

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	KEY ENERGY GROUP INC
		DATE OF NAME CHANGE:	19950217

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NATIONAL ENVIRONMENTAL GROUP INC
		DATE OF NAME CHANGE:	19921228

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	YANKEE COMPANIES INC
		DATE OF NAME CHANGE:	19891012

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BYERLOTZER JAMES J
		CENTRAL INDEX KEY:			0001227676

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08038
		FILM NUMBER:		05592422

	MAIL ADDRESS:	
		STREET 1:		6 DESTA DRIVE SUITE 4400
		CITY:			MILDLAND
		STATE:			TX
		ZIP:			79705
</SEC-HEADER>
<DOCUMENT>
<TYPE>5
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 5 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>5</documentType>

    <periodOfReport>2004-12-31</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <form3HoldingsReported>0</form3HoldingsReported>

    <form4TransactionsReported>0</form4TransactionsReported>

    <issuer>
        <issuerCik>0000318996</issuerCik>
        <issuerName>KEY ENERGY SERVICES INC</issuerName>
        <issuerTradingSymbol>KEG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001227676</rptOwnerCik>
            <rptOwnerName>BYERLOTZER JAMES J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>6 DESTA DRIVE, SUITE 4400</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MIDLAND</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>79705</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice Chairman</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-03-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3240</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16760</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">3,240 shares transferred as a gift to Mr. Byerlotzer's children who do not share the Reporting Person's household.</footnote>
        <footnote id="F2">Since the reporting person's last report, 20,000 shares previously owned directly were contributed to the Byerlotzer Management Trust prior to gifting shares to his children.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>James J. Byerlotzer</signatureName>
        <signatureDate>2005-02-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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