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


                        REPORT OF FOREIGN PRIVATE ISSUER

                                SEMIANNUAL REPORT
                    FROM APRIL 1, 2002 TO SEPTEMBER 30, 2002

                        PURSUANT TO RULE 13a-16 OR 15d-16
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934

                    For the six-month ended September 30, 2002

For the month of   January 10 ,  2003
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Commission File Number ___________________


                               MITSUI & CO., LTD.
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                 (Translation of registrant's name into English)

             2-1, OHTEMACHI 1-CHOME CHIYODA-KU, TOKYO 100-0004 JAPAN
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                    (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):
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Note: Regulation S-T Rule 101(b)(1) only permits the submission in paper of a
Form 6-K if submitted solely to provide an attached annual report to security
holders.

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):
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Note: Regulation S-T Rule 101(b)(7) only permits the submission in paper of a
Form 6-K if submitted to furnish a report or other document that the registrant
foreign private issuer must furnish and make public under the laws of the
jurisdiction in which the registrant is incorporated, domiciled or legally
organized (the registrant's "home country"), or under the rules of the home
country exchange on which the registrant's securities are traded, as long as the
report or other document is not a press release, is not required to be and has
not been distributed to the registrant's security holders, and, if discussing a
material event, has already been the subject of a Form 6-K submission or other
Commission filing on EDGAR.

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
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If "Yes" is marked, indicate below the file number assigned to the registrant
in connection with Rule 12g3-2(b): 82-
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                                   SIGNATURES

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


Date: January 10, 2003

                               MITSUI & CO., LTD.


                               By: /s/ Tasuku Kondo
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                                   Name:  Tasuku Kondo
                                   Title: Executive Director
                                          Senior Executive Managing Officer
                                          Chief Financial Officer