June 8, 2006

Securities and Exchange Commission
Division of Corporation Finance
Mr. Amit Pande
Assistant Chief Accountant
Washington, D.C. 20549

         Re:  Comment Letter of Securities and Exchange Commission
              BOK Financial Corporation
              Form 10-K for Fiscal Year Ended December 31, 2005
              Forms 10-Q for Quarter Ended March 31, 2006
              File No. 000-19341

Dear Mr. Pande:

In your letter  dated May 25,  2006 (the  "Comment  Letter")  you  provided  BOK
Financial Corporation (the "Company") with the following comment:

         Form 10-K for the Fiscal Year Ended December 31, 2005

         Independent Accountant Reports

          1.  Please  include  revised  reports  from  your  independent  public
          accountant  both  on  your  consolidated   financial   statements  and
          effectiveness  of  internal   control  over  financial   reporting  to
          correctly cross reference the March 10, 2006 report dates.  Currently,
          the last  paragraph  of each  report  refers to a March 1, 2006 report
          date.

In  response  to this  comment,  the  Company  has revised the date in the above
referenced  reports,  received a new consent from its auditors for the inclusion
of the  revised  reports,  and is herewith  filing an amended  form 10-K on form
10-K/A.

There were no other comments contained in the Comment Letter.

In addition to providing the above response, the Company hereby acknowledges the
following:

          i) the Company is  responsible  for the  adequacy  and accuracy of the
          disclosure in the filing;

          ii) staff  comments  or changes to  disclosure  in  response  to staff
          comments do not foreclose the  Commission  from taking any action with
          respect to the filing; and

          iii) the  Company  may not assert  staff  comments as a defense in any
          proceeding initiated by the Commission or any person under the federal
          securities laws of the United States.

If you have any further comments, or need additional information, please contact
myself at the contacts provided above or Tamara Wagman, counsel for the Company,
at (918) 583-9958. Thank you.


Sincerely,

/s/ Steven E. Nell

Steven E. Nell
Executive Vice President
Chief Financial Officer