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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001214804-10-000001.txt : 20100312
<SEC-HEADER>0001214804-10-000001.hdr.sgml : 20100312
<ACCEPTANCE-DATETIME>20100312120803
ACCESSION NUMBER:		0001214804-10-000001
CONFORMED SUBMISSION TYPE:	D/A
PUBLIC DOCUMENT COUNT:		1
ITEM INFORMATION:		Investment Company Act Section 3(c)
ITEM INFORMATION:		Section 3(c)(7)
FILED AS OF DATE:		20100312
DATE AS OF CHANGE:		20100312
EFFECTIVENESS DATE:		20100312

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HALCYON FUND LP
		CENTRAL INDEX KEY:			0001214804
		IRS NUMBER:				133093796
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		D/A
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	021-51993
		FILM NUMBER:		10676532

	BUSINESS ADDRESS:	
		STREET 1:		477 MADISON AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022
		BUSINESS PHONE:		2123039400

	MAIL ADDRESS:	
		STREET 1:		477 MADISON AVENUE, 8TH FLOOR
		CITY:			NEW YORK
		STATE:			X1
		ZIP:			10022
</SEC-HEADER>
<DOCUMENT>
<TYPE>D/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0603</schemaVersion>

    <submissionType>D/A</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001214804</cik>
        <entityName>HALCYON FUND LP</entityName>
        <issuerAddress>
            <street1>477 MADISON AVENUE</street1>
            <city>NEW YORK</city>
            <stateOrCountry>NY</stateOrCountry>
            <zipCode>10022</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>2123039400</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <previousName>Halcyon Investments</previousName>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <overFiveYears>true</overFiveYears>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>John</firstName>
                <middleName>M.</middleName>
                <lastName>Bader</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>477 Madison Avenue, 8th Floor</street1>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <zipCode>10022</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>John Bader is a principal of the Investment Manager of the issuer.</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Thomas</firstName>
                <middleName>Paul</middleName>
                <lastName>Hirschfeld</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>477 Madison Avenue, 8th Floor</street1>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <zipCode>10022</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Thomas Hirschfeld is a principal of the Investment Manager of the issuer.</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Kevah</firstName>
                <middleName>Ross</middleName>
                <lastName>Konner</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>477 Madison Avenue, 8th Floor</street1>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <zipCode>10022</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Kevah Konner is a principal of the Investment Manager of the issuer.</relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Hedge Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <aggregateNetAssetValueRange>Over $100,000,000</aggregateNetAssetValueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>3C</item>
            <item>3C.7</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>true</isAmendment>
                <previousAccessionNumber>0001214804-09-000003</previousAccessionNumber>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>1982-01-01</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>true</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isPooledInvestmentFundType>true</isPooledInvestmentFundType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>5000000</minimumInvestmentAccepted>
        <salesCompensationList>
            <recipient>
                <recipientName>Merrill Lynch Alternative Investments LLC</recipientName>
                <recipientCRDNumber>105067</recipientCRDNumber>
                <associatedBDName>None</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>4 World Financial Center</street1>
                    <street2>250 Vesey Street, 6th Floor</street2>
                    <city>New York</city>
                    <stateOrCountry>NY</stateOrCountry>
                    <zipCode>10080</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <value>All States</value>
                </statesOfSolicitationList>
            </recipient>
        </salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>Indefinite</totalOfferingAmount>
            <totalAmountSold>144000000</totalAmountSold>
            <totalRemaining>Indefinite</totalRemaining>
            <clarificationOfResponse>Re #13: &quot;Total Amount Sold&quot; reflects current approximate assets under management. Re #14 (below): The number of investors provided reflects current investors and may include sales to US and non-US persons. Investment includes contribution of the GP.</clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>36</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>444980</dollarAmount>
                <isEstimate>true</isEstimate>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse>Such soliciation fees are paid by the Investment Manager. No proceeds of the offering are used to pay these fees.</clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse>Fund Investments, Management and Performance fees.</clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>HALCYON FUND LP</issuerName>
                <signatureName>Thomas P. Hirschfeld</signatureName>
                <nameOfSigner>Thomas P. Hirschfeld</nameOfSigner>
                <signatureTitle>Managing Principal &amp; Chief Operating Officer</signatureTitle>
                <signatureDate>2010-03-12</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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