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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,
 UIX2qx9TmMIf3pdKNzB2o3P1EmTgdX9cbOynSrxSE8MYHNTdNauppvP4gxHnpSic
 fAqtHx0/kva8oMCOnaXMHw==

<SEC-DOCUMENT>0000893160-04-000005.txt : 20040727
<SEC-HEADER>0000893160-04-000005.hdr.sgml : 20040727
<ACCEPTANCE-DATETIME>20040726151309
ACCESSION NUMBER:		0000893160-04-000005
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040721
FILED AS OF DATE:		20040726

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Brown Thomas D
		CENTRAL INDEX KEY:			0001298084

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20931
		FILM NUMBER:		04930802

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		800-227-2155

	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>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2004-07-21</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001298084</rptOwnerCik>
            <rptOwnerName>Brown Thomas D</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>

    <ownerSignature>
        <signatureName>Nicholas Malden as Attorney in Fact for Thomas D Brown</signatureName>
        <signatureDate>2004-07-26</signatureDate>
    </ownerSignature>
</ownershipDocument>

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