UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION

                              Washington, DC 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):
                                December 21, 2005


                            BOK FINANCIAL CORPORATION
             (Exact name of registrant as specified in its charter)


                           Commission File No. 0-19341
                        
                 Oklahoma                                 73-1373454
       (State or other jurisdiction                     (IRS Employer
    of Incorporation or Organization)                Identification No.)

          Bank of Oklahoma Tower                    
              P.O. Box 2300
             Tulsa, Oklahoma                                74192
 (Address of Principal Executive Offices)                 (Zip Code)
 
                                 (918) 588-6000
              (Registrant's telephone number, including area code)



Check the appropriate box below if the Form 8-K filing 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)).




                    INFORMATION TO BE INCLUDED IN THE REPORT

ITEM 8.01  Other Events

     BOK  Financial  Corporation  (the  "Company"),   through  its  wholly-owned
subsidiary,  Bank of Oklahoma,  N.A.  approved  modifications  to the retirement
benefit plans offered to its employees.  The  objectives of these  modifications
are to provide  competitive  retirement  benefits that reward long-term employee
performance  and  provide  employees  with more  control  over their  retirement
savings. These modifications will become effective April 1, 2006.

     Changes to Company's Thrift Plans include increasing the maximum percentage
of  employee  contribution  subject  to  employer  matching  from  5%  to  6% of
compensation  as  defined  by the  plans,  increasing  the  employer's  matching
contributions based on years of service, and implementing a maximum non-elective
annual   contribution  of  $750  for  certain   employees.   Employer   matching
contributions  will now range from 50 cents per dollar  contributed by employees
with less than four years of service to $2 per dollar  contributed  by employees
with 15 or more years of service.  In addition,  the maximum after-tax  employee
contribution  has been increased from 5% to 6% of compensation as defined by the
plans.

     The Company also elected to curtail  accruals for future  service under its
defined-benefit  Pension  Plan.  Interest  will continue to accrue on employees'
account balances as provided by the Pension Plan.

     The  Company  will incur a charge of  approximately  $500,000 in the fourth
quarter of 2005 for the  curtailment of its Pension Plan. The combined effect of
the  modifications  is not  expected  to have a  significant  impact  on  future
earnings or liquidity.


                                    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.


                                     BOK FINANCIAL CORPORATION


                                     By:      /s/ Steven E. Nell              
                                         -----------------------------------
                                         Steven E. Nell
                                         Executive Vice President
                                         Chief Financial Officer

Date:    December 21, 2005   
      ------------------------