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

    <schemaVersion>X0704</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001275589</cik>
        <entityName>ECOSYNTHETIX INC</entityName>
        <issuerAddress>
            <street1>3900 COLLINS STE. 1018</street1>
            <city>LANSING</city>
            <stateOrCountry>MI</stateOrCountry>
            <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
            <zipCode>48910</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>517-336-4649</issuerPhoneNumber>
        <jurisdictionOfInc>MICHIGAN</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Corporation</entityType>
        <yearOfInc>
            <overFiveYears>true</overFiveYears>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>John</firstName>
                <lastName>van Leeuwen</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>3900 Collins Road, Ste 1018</street1>
                <city>Lansing</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48910</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Robert</firstName>
                <lastName>Haire</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>3900 Collins Road, Ste 1018</street1>
                <city>Lansing</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48910</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Steven</firstName>
                <lastName>Bloembergen</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>3900 Collins Road, Ste 1018</street1>
                <city>Lansing</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48910</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>David</firstName>
                <lastName>Colcleugh</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>3900 Collins Road, Ste 1018</street1>
                <city>Lansing</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48910</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>John</firstName>
                <lastName>Barker</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>3900 Collins Road, Ste 1018</street1>
                <city>Lansing</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48910</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>James</firstName>
                <lastName>Sayre</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>3900 Collins Road, Ste 1018</street1>
                <city>Lansing</city>
                <stateOrCountry>MI</stateOrCountry>
                <stateOrCountryDescription>MICHIGAN</stateOrCountryDescription>
                <zipCode>48910</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Other Technology</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2010-11-10</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>25000</minimumInvestmentAccepted>
        <salesCompensationList>
            <recipient>
                <recipientName>Canaccord Genuity Corp.</recipientName>
                <recipientCRDNumber>None</recipientCRDNumber>
                <associatedBDName>None</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>161 Bay Street, Suite 3000</street1>
                    <city>Toronto</city>
                    <stateOrCountry>A6</stateOrCountry>
                    <stateOrCountryDescription>ONTARIO, CANADA</stateOrCountryDescription>
                    <zipCode>M5J 2S1</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <state>CT</state>
                    <description>CONNECTICUT</description>
                    <state>MA</state>
                    <description>MASSACHUSETTS</description>
                    <state>MI</state>
                    <description>MICHIGAN</description>
                    <state>NY</state>
                    <description>NEW YORK</description>
                    <state>TX</state>
                    <description>TEXAS</description>
                </statesOfSolicitationList>
                <foreignSolicitation>false</foreignSolicitation>
            </recipient>
        </salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>7156800</totalOfferingAmount>
            <totalAmountSold>7156800</totalAmountSold>
            <totalRemaining>0</totalRemaining>
            <clarificationOfResponse>Total equity sold was $30,240,000, however, the amount sold in the U.S. under Rule 506 is listed above.  The remainder of the issue was sold out of the U.S.</clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>7</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>393907</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse>Total sales commission for the sale of $30,240,000 was $1,664,400 plus expenses of $128,000.</clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>ECOSYNTHETIX INC</issuerName>
                <signatureName>Robert Haire</signatureName>
                <nameOfSigner>Robert Haire</nameOfSigner>
                <signatureTitle>CFO</signatureTitle>
                <signatureDate>2010-11-23</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
