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Exhibit 32.1

Certification of Chief Executive Officer of GFI Group Inc.
Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002

        In connection with the Annual Report of GFI Group Inc. (the "Company") on Form 10-K for the fiscal year ended December 31, 2004 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Michael Gooch, Chairman and Chief Executive Officer of the Company, certify, pursuant to the 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

1.

The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and



2.

The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: March 31, 2005

/s/  MICHAEL GOOCH Michael Gooch
Chairman of the Board
Chief Executive Officer

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Certification of Chief Executive Officer of GFI Group Inc. Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002