-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 K0CBH6A62a1fsMfO51kY3RktNFXvUAsb3A6yvEuUvkhxdiMHzRyz302xF+1tkl+z
 2vm5GZBOZjunMZUqelJMPQ==

<SEC-DOCUMENT>0000897069-09-000104.txt : 20090123
<SEC-HEADER>0000897069-09-000104.hdr.sgml : 20090123
<ACCEPTANCE-DATETIME>20090123143815
ACCESSION NUMBER:		0000897069-09-000104
CONFORMED SUBMISSION TYPE:	D
PUBLIC DOCUMENT COUNT:		1
ITEM INFORMATION:		Rule 506
FILED AS OF DATE:		20090123
DATE AS OF CHANGE:		20090123
EFFECTIVENESS DATE:		20090123

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MITHRIDION INC
		CENTRAL INDEX KEY:			0001370742
		IRS NUMBER:				201927119
		STATE OF INCORPORATION:			WI
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		D
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	021-92780
		FILM NUMBER:		09541769

	BUSINESS ADDRESS:	
		STREET 1:		505 SCIENCE DRIVE
		STREET 2:		SUITE C
		CITY:			MADISON
		STATE:			WI
		ZIP:			53711
		BUSINESS PHONE:		(608) 443-2432

	MAIL ADDRESS:	
		STREET 1:		505 SCIENCE DRIVE
		STREET 2:		SUITE C
		CITY:			MADISON
		STATE:			WI
		ZIP:			53711
</SEC-HEADER>
<DOCUMENT>
<TYPE>D
<SEQUENCE>1
<FILENAME>primary_doc.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0201</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001370742</cik>
        <entityName>MITHRIDION INC</entityName>
        <issuerAddress>
            <street1>505 SCIENCE DRIVE</street1>
            <street2>SUITE C</street2>
            <city>MADISON</city>
            <stateOrCountry>WI</stateOrCountry>
            <zipCode>53711</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>(608) 443-2432</issuerPhoneNumber>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <jurisdictionOfInc>WI</jurisdictionOfInc>
        <entityType>Corporation</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2004</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Trevor</firstName>
                <middleName>M.</middleName>
                <lastName>Twose</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>505 Science Drive</street1>
                <street2>Suite C</street2>
                <city>Madison</city>
                <stateOrCountry>WI</stateOrCountry>
                <zipCode>53711</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
                <relationship>Promoter</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Patti</firstName>
                <middleName>A.</middleName>
                <lastName>Twose</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>505 Science Drive</street1>
                <street2>Suite C</street2>
                <city>Madison</city>
                <stateOrCountry>WI</stateOrCountry>
                <zipCode>53711</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>William</firstName>
                <middleName>S.</middleName>
                <lastName>Messer</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>2019 Potomac Drive</street1>
                <street2></street2>
                <city>Toledo</city>
                <stateOrCountry>OH</stateOrCountry>
                <zipCode>43607</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Wayne</firstName>
                <middleName>P.</middleName>
                <lastName>Hoss</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>4154 Halifax Road</street1>
                <street2></street2>
                <city>Toledo</city>
                <stateOrCountry>OH</stateOrCountry>
                <zipCode>43606</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Paul</firstName>
                <middleName>M.</middleName>
                <lastName>Weiss</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>505 South Rosa Road</street1>
                <street2>Suite 201</street2>
                <city>Madison</city>
                <stateOrCountry>WI</stateOrCountry>
                <zipCode>53719</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>John</firstName>
                <middleName>P.</middleName>
                <lastName>Neis</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>505 South Rosa Road</street1>
                <street2>Suite 201</street2>
                <city>Madison</city>
                <stateOrCountry>WI</stateOrCountry>
                <zipCode>53719</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Biotechnology</industryGroupType>
        </industryGroup>
        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2009-01-09</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>6016988</totalOfferingAmount>
            <totalAmountSold>2908499</totalAmountSold>
            <totalRemaining>3108489</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>4</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>259000</dollarAmount>
                <isEstimate>true</isEstimate>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>MITHRIDION INC</issuerName>
                <signatureName>Patti A. Twose</signatureName>
                <nameOfSigner>Patti A. Twose</nameOfSigner>
                <signatureTitle>Secretary and Treasurer</signatureTitle>
                <signatureDate>2009-01-23</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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