<SUBMISSION>
<ACCESSION-NUMBER>0001513162-14-000632
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20141121
<FILING-DATE>20141121
<DATE-OF-FILING-DATE-CHANGE>20141121
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>CLEAN DIESEL TECHNOLOGIES INC
<CIK>0000949428
<ASSIGNED-SIC>3564
<IRS-NUMBER>061393453
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>1621 FISKE PLACE
<CITY>OXNARD
<STATE>CA
<ZIP>93033
<PHONE>805 639 9458
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>1621 FISKE PLACE
<CITY>OXNARD
<STATE>CA
<ZIP>93033
</MAIL-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>Park Mungo
<CIK>0001474363
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>001-33710
<FILM-NUMBER>141244069
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>C/O CLEAN DIESEL TECHNOLOGIES, INC.
<STREET2>1621 FISKE PLACE
<CITY>OXNARD
<STATE>CA
<ZIP>93033
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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        <issuerName>CLEAN DIESEL TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>CDTI</issuerTradingSymbol>
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            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>93033</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
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            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
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    <footnotes>
        <footnote id="F1">Shares of Common Stock acquired upon settlement of Restricted Share Units (&quot;RSUs&quot;) granted May 21, 2014 pursuant to the Clean Diesel Technologies, Inc. (&quot;CDTI&quot;) Stock Incentive Plan.</footnote>
        <footnote id="F2">Each RSU represents a contingent right to receive one share of CDTI common stock.</footnote>
        <footnote id="F3">RSU vests as to 50% on November 21, 2014 and 50% on the earlier of 1) May 21, 2015, or 2) immediately prior to the commencement of the Issuer's 2015 annual meeting of stockholders, in each case as long as the reporting person has continuously remained a director of, or consultant to, the Issuer through such date. Issuance to occur as soon as practicable following the date of vesting and subject to compliance with Issuer's Insider Trading Policy, but in all cases within two and one-half months following the end of the Issuer's tax year that includes the date such RSUs vest.</footnote>
        <footnote id="F4">RSU vests as to 100% on November 21, 2014. Issuance to occur as soon as practicable following the date of vesting and subject to compliance with Issuer's Insider Trading Policy, but in all cases within two and one-half months following the end of the Issuer's tax year that includes the date such RSUs vest.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Kristi Cushing for Mungo Park</signatureName>
        <signatureDate>2014-11-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
