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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001437317-10-000012.txt : 20100824
<SEC-HEADER>0001437317-10-000012.hdr.sgml : 20100824
<ACCEPTANCE-DATETIME>20100824175831
ACCESSION NUMBER:		0001437317-10-000012
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100820
FILED AS OF DATE:		20100824
DATE AS OF CHANGE:		20100824

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LYNCH G PATRICK
		CENTRAL INDEX KEY:			0001258554

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11038
		FILM NUMBER:		101035998

	MAIL ADDRESS:	
		STREET 1:		547 LONESOME PINE TRAIL
		CITY:			LINO LAKES
		STATE:			MN
		ZIP:			55014

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NORTHERN TECHNOLOGIES INTERNATIONAL CORP
		CENTRAL INDEX KEY:			0000875582
		STANDARD INDUSTRIAL CLASSIFICATION:	COATING, ENGRAVING & ALLIED SERVICES [3470]
		IRS NUMBER:				410857886
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0831

	BUSINESS ADDRESS:	
		STREET 1:		4201 WOODLAND ROAD
		STREET 2:		PO BOX 69
		CITY:			CIRCLE PINES
		STATE:			MN
		ZIP:			55014
		BUSINESS PHONE:		(763) 225-6601

	MAIL ADDRESS:	
		STREET 1:		4201 WOODLAND ROAD
		STREET 2:		PO BOX 69
		CITY:			CIRCLE PINES
		STATE:			MN
		ZIP:			55014

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NORTHERN INSTRUMENTS CORP
		DATE OF NAME CHANGE:	19930328
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-08-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000875582</issuerCik>
        <issuerName>NORTHERN TECHNOLOGIES INTERNATIONAL CORP</issuerName>
        <issuerTradingSymbol>NTIC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001258554</rptOwnerCik>
            <rptOwnerName>LYNCH G PATRICK</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>547 LONESOME PINE TRAIL</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LINO LAKES</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55014</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President and CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-08-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>859</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.69</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>628983</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares are held directly by Inter Alia Holding Company of which G. Patrick Lynch is an officer and stockholder.  Mr. G. Patrick Lynch disclaims beneficial ownership of the shares held by Inter Alia Holding Company, except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/G. Patrick Lynch</signatureName>
        <signatureDate>2010-08-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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