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<SEC-DOCUMENT>0001238201-09-000020.txt : 20091112
<SEC-HEADER>0001238201-09-000020.hdr.sgml : 20091111
<ACCEPTANCE-DATETIME>20091112190205
ACCESSION NUMBER:		0001238201-09-000020
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091109
FILED AS OF DATE:		20091112
DATE AS OF CHANGE:		20091112

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PRO DEX INC
		CENTRAL INDEX KEY:			0000788920
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				841261240
		STATE OF INCORPORATION:			CO
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		2361 MCGAW AVENUE
		CITY:			IRVINE
		STATE:			CA
		ZIP:			92614
		BUSINESS PHONE:		949-769-3200

	MAIL ADDRESS:	
		STREET 1:		2361 MCGAW AVENUE
		CITY:			IRVINE
		STATE:			CA
		ZIP:			92614

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			COSS RONALD G
		CENTRAL INDEX KEY:			0001251504

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14942
		FILM NUMBER:		091178647

	MAIL ADDRESS:	
		STREET 1:		3 OVERLOOK DR
		CITY:			NEWPORT COAST
		STATE:			CA
		ZIP:			92657
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2009-11-09</periodOfReport>

    <dateOfOriginalSubmission>2009-11-09</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000788920</issuerCik>
        <issuerName>PRO DEX INC</issuerName>
        <issuerTradingSymbol>PDEx</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001251504</rptOwnerCik>
            <rptOwnerName>COSS RONALD G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3 OVERLOOK DR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NEWPORT COAST</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92657</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <otherText>See footnote 1</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Pro-Dex Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2009-11-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>6000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.66</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>956879</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Trust (I)</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">As a result of his most recent transactions, Mr. Coss is no longer a 10% shareholder.</footnote>
        <footnote id="F2">This amendment shows that as of November 9, 2009 Mr. Coss owned 956,879 shares of common stock, which reflects the expiration of 100,000 warrants on June 30, 2009.  This amendment also affects the Form 4s filed for Mr. Coss on November 6, 2009, October 20, 2009, October 16, 2009, October 9, 2009, August 11, 2009 and August 5, 2009.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Jeff Ritchey</signatureName>
        <signatureDate>2009-11-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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