<SUBMISSION>
<ACCESSION-NUMBER>0001110803-05-000032
<TYPE>4/A
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20050408
<FILING-DATE>20050415
<DATE-OF-FILING-DATE-CHANGE>20050415
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>ILLUMINA INC
<CIK>0001110803
<ASSIGNED-SIC>3826
<IRS-NUMBER>330804655
<STATE-OF-INCORPORATION>CA
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>9885 TOWNE CENTRE DRIVE
<STREET2>.
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
<PHONE>8582024500
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>9885 TOWN CENTRE DRIVE
<STREET2>.
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
</MAIL-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>Kersey Alan
<CIK>0001323528
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4/A
<ACT>34
<FILE-NUMBER>000-30361
<FILM-NUMBER>05752520
</FILING-VALUES>
<BUSINESS-ADDRESS>
<PHONE>858-202-4606
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>9885 TOWNE CENTRE DRIVE
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>edgardoc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2005-04-08</periodOfReport>

    <dateOfOriginalSubmission>2005-04-12</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001110803</issuerCik>
        <issuerName>ILLUMINA INC</issuerName>
        <issuerTradingSymbol>ILMN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001323528</rptOwnerCik>
            <rptOwnerName>Kersey Alan</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>9885 TOWNE CENTRE DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92121</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>V.P. &amp; Site Manager</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Incentive Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.833</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-04-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10761</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-04-08</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-12-19</value>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>10761</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10761</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">2,742 of the shares subject to the option are exercisable on the date indicated.  Of the 8,019 remaining option shares, 243 shares become exercisable at the end of each month beginning April 31, 2005, subject to the reporting person's continuing to be a Service Provider on such dates; however, the option may become fully exercisable under certain circumstances.</footnote>
        <footnote id="F2">The Expiration Date was incorrectly reported on the original Form 4.</footnote>
        <footnote id="F3">Received in exchange for an employee stock option to acquire 7.864 shares of common stock of CyVera Corporation, a Delaware corporation (&quot;CyVera&quot;), at an exercise price of $2,508 per share, upon the effective time of Illumina's acquisition of CyVera pursuant to the Agreement and Plan of Merger entered into as of February 22, 2005, by and among Illumina, a wholly-owned subsidiary of Illumina and CyVera.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Connie Brick  For: Alan D. Kersey</signatureName>
        <signatureDate>2005-04-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
