UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT

                       PURSUANT TO SECTION 13 OR 15(D) OF
                       THE SECURITIES EXCHANGE ACT OF 1934

      Date of Report (Date of earliest event reported): September 12, 2005
                                                        ------------------

                       FIRST NIAGARA FINANCIAL GROUP, INC.
               --------------------------------------------------
               (Exact Name of Registrant as Specified in Charter)

           Delaware                    000-23975                  42-1556195
- ----------------------------     ---------------------       -------------------
(State or Other Jurisdiction     (Commission File No.)        (I.R.S. Employer
      of Incorporation)                                      Identification No.)

6950 South Transit Road, P.O. Box 514, Lockport, New York         14095-0514
- ---------------------------------------------------------         ----------
(Address of Principal Executive Offices)                          (Zip Code)

Registrant's telephone number, including area code: (716) 625-7500
                                                    --------------

                                 Not Applicable
                                 --------------
          (Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K is intended to simultaneously
satisfy the filing obligation of the registrant under any of the following
provisions:

|_|   Written communications pursuant to Rule 425 under the Securities Act (17
      CFR 230.425)

|_|   Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
      240.14a-12)

|_|   Pre-commencement communications pursuant to Rule 14d-2(b) under the
      Exchange Act (17 CFR 240.14d-2(b))

|_|   Pre-commencement communications pursuant to Rule 13e-4(c) under the
      Exchange Act (17 CFR 240.13e-4 (c))



Item 8.01 Other Events.

On September 12, 2005, First Niagara Financial Group, Inc. (the "Company")
issued a press release disclosing that it has acquired Burke Group, Inc., an
employee benefits administration and compensation consulting firm that has
offices in Rochester and Syracuse and serves clients throughout First Niagara's
upstate New York footprint. Under agreement by both parties financial terms of
the acquisition were not disclosed. A copy of the press release is filed as
exhibit 99.1 to this report.

Item 9.01 Financial Statements and Exhibits

(a)   Not Applicable.

(b)   Not Applicable.

(c)   Exhibits.

      Exhibit No.         Description
      -----------         -----------

      99.1                Press release dated September 12, 2005



                                   SIGNATURE

      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, hereunto duly authorized.

                                            FIRST NIAGARA FINANCIAL GROUP, INC.


DATE: September 12, 2005                    By: /s/ John R. Koelmel
                                                --------------------------------
                                                John R. Koelmel
                                                Chief Financial Officer
                                                (Duly authorized representative)