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

    <schemaVersion>X0707</schemaVersion>

    <submissionType>D/A</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001612343</cik>
        <entityName>Essex Woodlands Fund IX, L.P.</entityName>
        <issuerAddress>
            <street1>21 WATERWAY AVENUE, SUITE 225</street1>
            <city>THE WOODLANDS</city>
            <stateOrCountry>TX</stateOrCountry>
            <stateOrCountryDescription>TEXAS</stateOrCountryDescription>
            <zipCode>77380</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>281-364-1555</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2014</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Martin</firstName>
                <middleName>P.</middleName>
                <lastName>Sutter</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>21 Waterway Avenue, Suite 225</street1>
                <city>The Woodlands</city>
                <stateOrCountry>TX</stateOrCountry>
                <stateOrCountryDescription>TEXAS</stateOrCountryDescription>
                <zipCode>77380</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Petri</firstName>
                <middleName>T.</middleName>
                <lastName>Vainio, MD, PhD</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>Berkeley Square House</street1>
                <street2>Berkeley Square</street2>
                <city>London</city>
                <stateOrCountry>X0</stateOrCountry>
                <stateOrCountryDescription>UNITED KINGDOM</stateOrCountryDescription>
                <zipCode>W1J 6BR</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Ron</firstName>
                <lastName>Eastman</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>335 Bryant Street, 3rd Floor</street1>
                <city>Palo Alto</city>
                <stateOrCountry>CA</stateOrCountry>
                <stateOrCountryDescription>CALIFORNIA</stateOrCountryDescription>
                <zipCode>94301</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Steve</firstName>
                <lastName>Wiggins</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>280 Park Avenue, 27th Floor East</street1>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10017</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Richard</firstName>
                <middleName>Scott</middleName>
                <lastName>Barry</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>280 Park Avenue, 27th Floor East</street1>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10017</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Private Equity Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06b</item>
            <item>3C</item>
            <item>3C.7</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>true</isAmendment>
                <previousAccessionNumber>0001612343-15-000001</previousAccessionNumber>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2014-06-17</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>true</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isPooledInvestmentFundType>true</isPooledInvestmentFundType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList>
            <recipient>
                <recipientName>Eaton Partners, LLC</recipientName>
                <recipientCRDNumber>31170</recipientCRDNumber>
                <associatedBDName>None</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>131 Rowayton Avenue</street1>
                    <city>Rowayton</city>
                    <stateOrCountry>CT</stateOrCountry>
                    <stateOrCountryDescription>CONNECTICUT</stateOrCountryDescription>
                    <zipCode>068553</zipCode>
                </recipientAddress>
                <statesOfSolicitationList></statesOfSolicitationList>
                <foreignSolicitation>true</foreignSolicitation>
            </recipient>
        </salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>750000000</totalOfferingAmount>
            <totalAmountSold>458100000</totalAmountSold>
            <totalRemaining>291900000</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>25</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>5600000</dollarAmount>
                <isEstimate>true</isEstimate>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>10000000</dollarAmount>
                <isEstimate>true</isEstimate>
            </grossProceedsUsed>
            <clarificationOfResponse>Annual management fee payable to an affiliate.  Amount to be paid, number of years to be paid and extent to be paid out of gross proceeds unknown at this time.</clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Essex Woodlands Fund IX, L.P.</issuerName>
                <signatureName>/s/ Richard Scott Barry</signatureName>
                <nameOfSigner>Richard Scott Barry</nameOfSigner>
                <signatureTitle>Managing Director</signatureTitle>
                <signatureDate>2016-07-18</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>