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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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 R0jmBRgIqjtF7fiA+mN7Dw==

<SEC-DOCUMENT>0000893160-04-000018.txt : 20041230
<SEC-HEADER>0000893160-04-000018.hdr.sgml : 20041230
<ACCEPTANCE-DATETIME>20041230140921
ACCESSION NUMBER:		0000893160-04-000018
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041228
FILED AS OF DATE:		20041230
DATE AS OF CHANGE:		20041230

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WEERSING JAMES R
		CENTRAL INDEX KEY:			0001051711

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20931
		FILM NUMBER:		041233576

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		8019751191

	MAIL ADDRESS:	
		STREET 1:		1910 INNOVATION PARK DRIVE
		CITY:			TUCSON
		STATE:			AZ
		ZIP:			85737

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			VENTANA MEDICAL SYSTEMS INC
		CENTRAL INDEX KEY:			0000893160
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				942976937
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1910 INNOVATION PARK DRIVE
		CITY:			TUCSON
		STATE:			AZ
		ZIP:			85737
		BUSINESS PHONE:		800-227-2155

	MAIL ADDRESS:	
		STREET 1:		1910 INNOVATION PARK DRIVE
		CITY:			TUCSON
		STATE:			AZ
		ZIP:			85737
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-12-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000893160</issuerCik>
        <issuerName>VENTANA MEDICAL SYSTEMS INC</issuerName>
        <issuerTradingSymbol>VMSI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001051711</rptOwnerCik>
            <rptOwnerName>WEERSING JAMES R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1910 INNOVATION PARK DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TUCSON</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85737</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Options (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>67.46</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-12-28</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4574</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>67.46</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2004-12-28</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-12-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>4574</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4574</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <ownerSignature>
        <signatureName>Nicholas Malden as attorney in fact for James Weersing</signatureName>
        <signatureDate>2004-12-30</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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