Exhibit 32(a)
                      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 period ended September 30, 2004, 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/ Rick Green                                        November 5, 2004
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    Rick Green                                            Date
    President and Chief Executive Officer
    (Principal Executive Officer)