June 6, 2011

Via EDGAR

Ms. Stephanie Hunsaker

Senior Assistant Chief Accountant

US Securities and Exchange Commission

Division of Corporation Finance

100 F Street, NE

Washington, DC 20549

RE:              BOK Financial Corporation

Form 10-K for the Fiscal Year Ended December 31, 2010

Filed February 28, 2011

File No. 001-19341

Dear Ms. Hunsaker:

This letter confirms receipt of your comment letter dated May 31, 2011 regarding our Form 10-K for the fiscal year ended December 31, 2010.  We will respond to your comments on or before July 5, 2011.

Please contact me at 918-588-6319 or John Morrow at 918-588-8673 if you have any questions.

Sincerely,

/s/ Steven E. Nell

-----------------------------------------------

Steven E. Nell

Executive Vice President and Chief Financial Officer

Cc:    John C. Morrow

         Tamara Wagman