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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 QI7EllBHR12OeD0fudJZkt/Zj6FVxgEKuFbMKtrnKQbzjQeEBwpRoVAxvrQLOTS0
 9fOxJ4+aq1/yMqBKxbCVIg==

<SEC-DOCUMENT>0000950103-05-001268.txt : 20050422
<SEC-HEADER>0000950103-05-001268.hdr.sgml : 20050422
<ACCEPTANCE-DATETIME>20050422121942
ACCESSION NUMBER:		0000950103-05-001268
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050418
FILED AS OF DATE:		20050422
DATE AS OF CHANGE:		20050422

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RITA MEDICAL SYSTEMS INC
		CENTRAL INDEX KEY:			0001056421
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845]
		IRS NUMBER:				943199149
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		967 N SHORELINE BLVD
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94013
		BUSINESS PHONE:		6503858500

	MAIL ADDRESS:	
		STREET 1:		967 NORTH SHORELINE BLVD
		CITY:			MOUNTAIN VIEW
		STATE:			CA
		ZIP:			94043

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HALSTED SCOTT S
		CENTRAL INDEX KEY:			0001204322

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-30959
		FILM NUMBER:		05766557

	MAIL ADDRESS:	
		STREET 1:		3000 SAND HILL RD
		STREET 2:		BLDG 4 STE 250
		CITY:			MENIO PARK
		STATE:			CA
		ZIP:			94025
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>halsted_ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-04-18</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001056421</issuerCik>
        <issuerName>RITA MEDICAL SYSTEMS INC</issuerName>
        <issuerTradingSymbol>RITA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001204322</rptOwnerCik>
            <rptOwnerName>HALSTED SCOTT S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>MORGAN STANLEY VENTURE PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>3000 SAND HILL RD., BUILDING 4 SUITE 250</rptOwnerStreet2>
            <rptOwnerCity>MENLO PARK,</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94025</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.07</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-04-18</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-04-18</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-18</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>42000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <ownerSignature>
        <signatureName>/s/ Scott S. Halsted</signatureName>
        <signatureDate>2005-04-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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