EXHIBIT 5
                  [LETTERHEAD OF GABLE & GOTWALS APPEARS HERE]



                                 January 20, 2000


ONEOK, Inc.
100 West Fifth Street
Tulsa, OK 74103

                               Re:  S-8 Registration Statement Under the
                                    Securities Act of 1933, Relating to the
                                    Shares of Common Stock of ONEOK, Inc. in
                                    Relation to the ONEOK, Inc. Employee Stock
                                    Purchase Plan

Gentlemen:

     We understand that ONEOK, Inc., an Oklahoma corporation (hereinafter
referred to as the "Company"), will file with the Securities and Exchange
Commission under the Securities Act of 1933, as amended, a Form S-8 Registration
Statement relating to the registration of shares of the Company's Common Stock
with respect to the ONEOK, Inc. Employee Stock Purchase Plan (the "Plan").

     We have examined (a) the above-mentioned Registration Statement which will
be filed with the Securities and Exchange Commission; (b) the Certificate of
Incorporation and Bylaws of the Company, as amended; (c) the ONEOK, Inc.
Employee Stock Purchase and the corporate actions taken by the Board of
Directors in connection with the Registration Statement and related matters; and
(d) such other corporate records, certificates of public officials and officers
of the Company and other documents as we have considered relevant to the matters
covered by this opinion.

     In connection with the foregoing, as counsel for the Company, we wish to
advise you as follows:

     3.   The Company is a corporation validly organized and existing under the
laws of the

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ONEOK, Inc.
January 20, 2000
Page 2

State of Oklahoma and is duly qualified to do business as a corporation in the
State of Kansas.

     4.   The filing of the above-mentioned Registration Statement has been duly
authorized by the proper corporate action on the part of the Company.

     5.   Assuming the Shares are being issued in compliance with the terms and
conditions of the Plan, when the certificates for the Shares have been executed
by the proper officer of the Company, countersigned by the Transfer Agent and
registered by the Registrar thereof, the certificates for such Shares will
represent, and the Shares will constitute, duly authorized, legally issued,
fully paid, non-assessable, valid and legal shares of the Common Stock of the
Company.

     We hereby consent to:

     1.   Being named in the Form S-8 Registration Statement and documents
constituting the prospectus which is being furnished, and in any amendments
thereto, as counsel for the Company, passing on legal matters in connection with
the issuance of the Common Stock to the Trustee under the Plan;

     2.   The making in the Form S-8 Registration Statement and documents
constituting the prospectus, and in any amendments thereto, of the statements
now appearing therein under the caption "interests of Named Experts and
Counsel," insofar as they are applicable to us; and

     3.   The filing of this opinion as an exhibit to the above-mentioned
Form S-8 Registration Statement.

                              Very truly yours,

                              GABLE & GOTWALS



                              By
                                    Donald A. Kihle

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