EXHIBIT 24

                                POWER OF ATTORNEY

                       FOR SEC FILINGS ON FORMS 4 AND 144
                           IN RESPECT OF SECURITIES OF
                             MF GLOBAL HOLDINGS LTD.

Pursuant to this power of attorney (the "Power of Attorney"), the undersigned,
an authorized representative of Man Group UK Limited, hereby constitutes and
appoints each of Anthony A. Lopez III, Per B. Chilstrom and Kristyn Walker or
any one of them acting alone, as its true and lawful attorney-in-fact and agent
(each, an "attorney-in-fact"), with full power of substitution and
resubstitution for it in its name and stead in any and all capacities, to sign
and file for and on its behalf, in respect of any acquisition, disposition or
other change in ownership of any shares of common stock, par value $1.00 per
share, of MF Global Holdings Ltd. (the "Company"), the following:

        (i)     any Statement of Changes of Beneficial Ownership of Securities
                on Form 4 to be filed with the United States Securities and
                Exchange Commission (the "SEC");

        (ii)    any Notice of Proposed Sale of Securities on Form 144 to be
                filed with the SEC; and

        (iii)   any and all agreements, certificates, receipts, or other
                documents in connection therewith.

The undersigned hereby gives full power and authority to the attorney-in-fact to
seek and obtain as the undersigned's representative and on the undersigned's
behalf, information on transactions in the Company's securities from any third
party, including brokers, employee benefit plan administrators and trustees, and
the undersigned hereby authorizes any such person to release such information to
the undersigned and approves and ratifies any such release of information.

The undersigned hereby grants unto such attorney-in-fact full power and
authority to do and perform each and every act and thing requisite and necessary
in connection with such matters and hereby ratifies and confirms all that any
such attorney-in-fact or substitute may do or cause to be done by virtue hereof.

The undersigned acknowledges that:

        (i)     neither the Company nor such attorney-in-fact assumes (i) any
                liability for the undersigned's responsibility to comply with
                the requirements of the United States Securities Act of 1933, as
                amended (the "Securities Act"), or the United States Securities
                Exchange Act of 1934, as amended (the "Exchange Act"), (ii) any
                liability of the undersigned for any failure to comply with such
                requirements or (iii) any obligation or liability of the
                undersigned for profit disgorgement under Section 16(b) of the
                Exchange Act; and

        (ii)    this Power of Attorney does not relieve the undersigned from
                responsibility for compliance with the undersigned's obligations
                under the Securities Act or the Exchange Act, including without
                limitation the reporting requirements under Section 16 of the
                Exchange Act.

This Power of Attorney shall remain in full force and effect until revoked by
the undersigned in a signed writing delivered to such attorney-in-fact.

IN WITNESS WHEREOF, the undersigned has executed this Power of Attorney.

Date:  May 26, 2010                    /s/ Kevin Hayes
                                        ---------------------------------------
                                        Name: Kevin Hayes
                                        Title: Director