-----BEGIN PRIVACY-ENHANCED MESSAGE-----
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,
 BTu3MZGYjK/m86wEDwvpA7g5NwBKo94UyoRIkSZSUDaXQB81GHTRVTSWlYHbin/8
 2FxgR8sp2Gm50fU7XtDTtw==

<SEC-DOCUMENT>0001179110-05-008730.txt : 20050503
<SEC-HEADER>0001179110-05-008730.hdr.sgml : 20050503
<ACCEPTANCE-DATETIME>20050503090630
ACCESSION NUMBER:		0001179110-05-008730
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050429
FILED AS OF DATE:		20050503
DATE AS OF CHANGE:		20050503

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AKSYS LTD
		CENTRAL INDEX KEY:			0000902600
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTROMEDICAL & ELECTROTHERAPEUTIC APPARATUS [3845]
		IRS NUMBER:				363890205
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		TWO MARRIOTT DR
		STREET 2:		STE 300
		CITY:			LIBERTYVILLE
		STATE:			IL
		ZIP:			60069
		BUSINESS PHONE:		8472476051

	MAIL ADDRESS:	
		STREET 1:		1113 S MILWAUKEE AVE
		STREET 2:		SUITE 300
		CITY:			LIBERTYVILLE
		STATE:			IL
		ZIP:			60048

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Pereira Brian JG
		CENTRAL INDEX KEY:			0001298146

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-28290
		FILM NUMBER:		05792910

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		617-497-2070

	MAIL ADDRESS:	
		STREET 1:		C/O ADVANCED MAGNETICS, INC.
		STREET 2:		61 MOONEY STREET
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02138
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-04-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000902600</issuerCik>
        <issuerName>AKSYS LTD</issuerName>
        <issuerTradingSymbol>AKSY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001298146</rptOwnerCik>
            <rptOwnerName>Pereira Brian JG</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>TWO MARRIOTT DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LINCOLNSHIRE</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60069</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option to purchase Aksys, Ltd. common stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.55</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-04-29</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>5000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.55</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-04-29</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Aksys, Ltd. Common</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>option to purchase Aksys, Ltd. common stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>2.55</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-04-29</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1333</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.55</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-07-01</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-07-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Aksys, Ltd. common stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1333</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6333</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Brian J. G. Pereira, M.D.</signatureName>
        <signatureDate>2005-05-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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