-----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,
 LRnKESIZLvt3gzILUYlR1/U3aD6t7P4TTAN6VQBEJN4v0JI0/tR51JVtLqdML4hb
 YSPlTpr03/vX4DhIg+IAFg==

<SEC-DOCUMENT>0001279392-08-000016.txt : 20080401
<SEC-HEADER>0001279392-08-000016.hdr.sgml : 20080401
<ACCEPTANCE-DATETIME>20080401163101
ACCESSION NUMBER:		0001279392-08-000016
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080401
FILED AS OF DATE:		20080401
DATE AS OF CHANGE:		20080401

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ENDOWMENT MASTER FUND L P
		CENTRAL INDEX KEY:			0001279392
		IRS NUMBER:				980393260
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4265 SAN FELIPE
		STREET 2:		8TH FLOOR
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77027
		BUSINESS PHONE:		7139934675

	MAIL ADDRESS:	
		STREET 1:		4265 SAN FELIPE
		STREET 2:		8TH FLOOR
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77027

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LINBECK ANDREW B
		CENTRAL INDEX KEY:			0001282433

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	811-21527
		FILM NUMBER:		08729775

	BUSINESS ADDRESS:	
		STREET 1:		DECHERT LLP
		STREET 2:		1775 I STREET NW
		CITY:			WASHINGTON
		STATE:			DC
		ZIP:			20006
		BUSINESS PHONE:		7139934675

	MAIL ADDRESS:	
		STREET 1:		4265 SAN FELIPE
		STREET 2:		SUITE 900
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77027
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-04-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001279392</issuerCik>
        <issuerName>ENDOWMENT MASTER FUND L P</issuerName>
        <issuerTradingSymbol>0</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001282433</rptOwnerCik>
            <rptOwnerName>LINBECK ANDREW B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>4265 SAN FELIPE</rptOwnerStreet1>
            <rptOwnerStreet2>8TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77027</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Co-Principal Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Limited Partnership Interests</value>
            </securityTitle>
            <transactionDate>
                <value>2008-04-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>100000</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <valueOwnedFollowingTransaction>
                    <value>1889390.6</value>
                    <footnoteId id="F2"/>
                </valueOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The securities are limited partnership interests. Holders are deemed to own a single interest, regardless of the amount of the interest.</footnote>
        <footnote id="F2">Mr. Linbeck has an indirect interest of $1,152,333.42 (estimated value as of 3/31/08) through affiliates of Salient Partners, L.P.'s investment in The Endowment Registered Fund, L.P. that invest in The Endowment Master Fund, L.P. He has $437,290.20 (estimated value as of 3/31/08) directly invested in The Endowment Registered Fund, L.P., which in turn invests in the issuer. He also has $299,766.99 (estimated value as of 3/31/08) directly invested in The Endowment TEI Fund, L.P., which in turn invests in the issuer.</footnote>
        <footnote id="F3">Through the investment of Salient Trust Co. in The Endowment Master Fund, L.P. via The Endowment Registered Fund, L.P., which in turn invests in the issuer. Salient Trust Co. is a wholly owned subsidiary of Salient Partners, L.P., in which Mr. Linbeck has an interest.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Andrew B Linbeck</signatureName>
        <signatureDate>2008-04-01</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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