EXHIBIT 32(b)

                      18 U.S.C. SECTION 1350 CERTIFICATIONS

I hereby certify pursuant to 18 U.S.C. ss. 1350, as adopted pursuant to
ss. 906 of the Sarbanes-Oxley Act of 2002, to the best of my knowledge and
belief, that the accompanying Form 10-K of Southwest Bancorp, Inc. ("Southwest")
for the annual period ended December 31, 2005, fully complies with the
requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934
(15 U.S.C. 78m or 78o(d)); and that the information contained in this Form 10-K
fairly presents, in all material respects, the financial condition and results
of operations of Southwest.


By: /s/ Kerby E. Crowell                                 March 10, 2006
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Kerby E. Crowell                                         Date
Executive Vice President, Chief Financial
Officer and Secretary
(Principal Financial Officer)