<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0603</schemaVersion>

    <submissionType>D/A</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001460962</cik>
        <entityName>CASTLEROCK FOCUS FUND LTD</entityName>
        <issuerAddress>
            <street1>CRAIGMUIR CHAMBERS</street1>
            <street2>BOX 71</street2>
            <city>ROAD TOWN, TORTOLA</city>
            <stateOrCountry>D8</stateOrCountry>
            <zipCode>BVI</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>284-494-2233</issuerPhoneNumber>
        <jurisdictionOfInc>VIRGIN ISLANDS, BRITISH</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Other</entityType>
        <entityTypeOtherDesc>British Virgin Islands business company</entityTypeOtherDesc>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2007</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Graham</firstName>
                <middleName>H.</middleName>
                <lastName>Cook</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>Bison Financial Services Ltd.</street1>
                <street2>Bison Court, Box 3460</street2>
                <city>Road Town, Tortola</city>
                <stateOrCountry>D8</stateOrCountry>
                <zipCode>BVI</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Colin</firstName>
                <lastName>Riegels</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>Harney Westwood &amp; Riegels</street1>
                <street2>Craigmuir Chambers, Box 71</street2>
                <city>Road Town, Tortola</city>
                <stateOrCountry>D8</stateOrCountry>
                <zipCode>BVI</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>David</firstName>
                <lastName>Bree</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>dms Management Ltd.</street1>
                <street2>Box 31910 SMB</street2>
                <city>Grand Cayman</city>
                <stateOrCountry>E9</stateOrCountry>
                <zipCode>KY1-1208</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Paul</firstName>
                <middleName>P.</middleName>
                <lastName>Tanico</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>c/o CastleRock Asset Management, Inc.</street1>
                <street2>101 Park Avenue, 23rd Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <zipCode>10178</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Promoter</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Ellen</firstName>
                <middleName>H.</middleName>
                <lastName>Adams</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>c/o CastleRock Asset Management, Inc.</street1>
                <street2>101 Park Avenue, 23rd Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <zipCode>10178</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Promoter</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Hedge Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <aggregateNetAssetValueRange>No Aggregate Net Asset Value</aggregateNetAssetValueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
            <item>3C</item>
            <item>3C.1</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>true</isAmendment>
                <previousAccessionNumber>9999999997-09-015563</previousAccessionNumber>
            </newOrAmendment>
            <dateOfFirstSale>
                <yetToOccur>true</yetToOccur>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>true</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isPooledInvestmentFundType>true</isPooledInvestmentFundType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>100000</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>Indefinite</totalOfferingAmount>
            <totalAmountSold>0</totalAmountSold>
            <totalRemaining>Indefinite</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>0</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>CASTLEROCK FOCUS FUND LTD</issuerName>
                <signatureName>/s/ David Bree</signatureName>
                <nameOfSigner>David Bree</nameOfSigner>
                <signatureTitle>Director</signatureTitle>
                <signatureDate>2010-03-24</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
