Exhibit 32(b)
                      18 U.S.C. Section 1350 Certification

I hereby certify pursuant to 18 U.S.C. ss. 1350, as adopted pursuant to ss. 906
of the Sarbanes-Oxley Act of 2003, to the best of my knowledge and belief, that
the accompanying Form 10-Q of Southwest Bancorp, Inc. ("Southwest") for the
quarterly and nine month periods ended September 30, 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-Q fairly presents, in all material respects, the financial condition and
results of operations of Southwest.


By: /s/ Kerby Crowell                             November 7, 2005
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    Kerby Crowell                                 Date
    Executive Vice President, Chief Financial
    Officer and Secretary
    (Principal Financial Officer)