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                                    FORM 6-K
                     U.S. SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                        REPORT OF FOREIGN PRIVATE ISSUER
                   PURSUANT TO RULE 13A-16 OR 15D-16 UNDER THE
                         SECURITIES EXCHANGE ACT OF 1934


                               dated July 8, 2005


                         Commission File Number 0-51373


                        CHEMGENEX PHARMACEUTICALS LIMITED
                    (Exact Name as Specified in its Charter)

                                       N/A
                       (Translation of Registrant's Name)

                                  Pigdons Road
                                   Waurn Ponds
                            P.O. Box 1069, Grovedale
                             Victoria 3216 Australia
                    (Address of principal executive offices)


         Indicate by check mark whether the registrant files or will file annual
reports under cover of Form 20-F or Form 40-F.

         Form 20-F    X    Form 40-F
                    -----            -----

         Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101(b)(1): _____

         Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101(b)(7): _____

         Indicate by check mark whether by furnishing the information contained
in this Form, the registrant is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

         Yes                        No  X
             ----                      ------

         If "Yes" is marked, indicate below the file number assigned to the
registrant in connection with Rule 12g3-2(b): Not applicable.

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                                   SIGNATURES

         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
the  registrant  has duly  caused  the  Report to be signed on its behalf by the
undersigned, thereunto duly authorized.


Date:  July 8, 2005

                                               CHEMGENEX PHARMACEUTICALS LIMITED


                                               By:/s/ Greg R. Collier
                                                  ------------------------------
                                                  Name:   Greg R. Collier
                                                  Title:     Managing Director




                                  EXHIBIT INDEX


Exhibit             Description of Exhibit
- -------             ----------------------

99.1                June 28, 2005 Press Release

99.2                June 27, 2005 Press Release