<SUBMISSION>
<ACCESSION-NUMBER>0001110803-08-000307
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20081009
<FILING-DATE>20081014
<DATE-OF-FILING-DATE-CHANGE>20081014
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>ILLUMINA INC
<CIK>0001110803
<ASSIGNED-SIC>3826
<IRS-NUMBER>330804655
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>0101
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>9885 TOWNE CENTRE DRIVE
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
<PHONE>8582024500
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>9885 TOWNE CENTRE DRIVE
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
</MAIL-ADDRESS>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>FLATLEY JAY T
<CIK>0001189130
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-30361
<FILM-NUMBER>081123880
</FILING-VALUES>
<MAIL-ADDRESS>
<STREET1>9885 TOWNE CENTRE DR
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
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    <footnotes>
        <footnote id="F1">Sale made pursuant to 10(b)5-1 plan.</footnote>
        <footnote id="F2">Weighted average sale price representing 7,500 shares sold ranging from $30.50 to $30.78 per share.</footnote>
        <footnote id="F3">Number of shares sold at each separate price will be made available to the SEC staff, the issuer, or a security holder of the issuer upon request.</footnote>
        <footnote id="F4">Weighted average sale price representing 1,666 shares sold ranging from $30.78 to $30.81 per share.</footnote>
        <footnote id="F5">Weighted average sale price representing 2,498 shares sold ranging from $30.81 to $30.85 per share.</footnote>
        <footnote id="F6">Weighted average sale price representing 1,666 shares sold ranging from $30.85 to $31.00 per share.</footnote>
        <footnote id="F7">Weighted average sale price representing 1,666 shares sold ranging from $31.00 to $31.50 per share.</footnote>
        <footnote id="F8">Weighted average sale price representing 1,666 shares sold ranging from $31.50 to $31.53 per share.</footnote>
        <footnote id="F9">Weighted average sale price representing 1,666 shares sold ranging from $31.53 to $31.85 per share.</footnote>
        <footnote id="F10">On Sept. 22, 2008, the common stock of Illumina Inc. split 2 for 1 resulting in Reporting Person's ownership of 439,813 additional shares.</footnote>
        <footnote id="F11">This option was previously reported as covering 150,000 shares at an exercise price of $2.77 per share, and was adjusted for the stock split that occurred on Sept. 22, 2008.</footnote>
        <footnote id="F12">This option was previously reported as covering 10,000 shares at an exercise price of $5.99 per share, and was adjusted for the stock split that occurred on Sept. 22, 2008.</footnote>
        <footnote id="F13">One-twelfth of shares subject to option became exercisable on 9/27/08. An additional one-twelfth shall become exercisable each full month thereafter, subject to Reporting Person's continuing to be a service provide on such date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Octavio Espinoza for Jay T. Flatley</signatureName>
        <signatureDate>2008-10-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
