Exhibit 21

BOK FINANCIAL CORPORATION

SUBSIDIARIES OF THE REGISTRANT

Banking Subsidiaries

BOKF, National Association (1)

Other subsidiaries of BOK Financial Corporation

BOK Capital Service Corporation

BOKF Capital Corporation

BOKF-CC (Collision Works), LLC

BOKF-CC (FSE), LLC

BOKF-CC (O2 Concepts), LLC

BOKF-CC (MCA), LLC

BOKF-CC (QRC), LLC

BOKF-CC (Switchgrass), LLC

BOKFCC Merchant Banking Fund I, LLC

BOKF Energy Fund Investment I, LLC

BOKF Equity, LLC

BOKF Private Equity Limited Partnership II

BOK Financial Insurance, Inc. (7)

BOK Financial Private Wealth, Inc. (5)

BOK Financial Securities, Inc.

Cavanal Hill Distributors, Inc.

CoBiz Risk Management, Inc. (8)

RMA Holdings, Inc. (7)

Switchgrass I, LLC

Switchgrass II, LLC

Switchgrass III, LLC

Switchgrass IV, LLC

Switchgrass V, LLC

Switchgrass VI, LLC

Switchgrass Holdings, LLC

Switchgrass Management, LLC

Switchgrass Properties, LLC

Subsidiaries of BOKF, National Association(1)

Affiliated BancServices, Inc.

Affiliated Financial Holding Co.

Affiliated Financial Insurance Agency, Inc.

AWREI, Inc. (7)

BancOklahoma Agri-Service Corporation

BOK Delaware, Inc. (3)

BOK Financial Asset Management, Inc. (2)

BOK Financial Equipment Finance, Inc.

BOK Financial Public Finance, Inc. (7)

BOK Funding Trust (3)

BOKFCDF Fund I, LLC

BOKF Community Development Fund, LLC

BOKF Community Development Fund II

BOKF Community Development Corporation

BOKF Petro Holding, LLC

BOKF Special Assets I, LLC

BOSC Agency, Inc. (Oklahoma)

BOSC Agency, Inc. (New Mexico) (4)

BOSC Agency, Inc. (Texas) (2)

Cavanal Hill Investment Management, Inc.

Cottonwood Valley Ventures, Inc.

CVV Management, Inc.

CVV Partnership, an Oklahoma General Partnership

Oklahoma New Markets Fund I, LLC

Western Real Estate Investors, Inc. (7)

All Subsidiaries listed above were incorporated in Oklahoma, except as noted.

(1) Chartered by the United States Government

(2) Incorporated in Texas

(3) Incorporated in Delaware

(4) Incorporated in New Mexico

(5) Incorporated in Colorado

(6) Incorporated in Kansas

(7) Incorporated in Colorado

(8) Incorporated in Nevada