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                                  EXHIBIT 4.3

                 BANCFIRST CORPORATION NON-EMPLOYEE DIRECTORS'
                               STOCK OPTION PLAN



1.   PURPOSE. The BancFirst Corporation Non-Employee Directors' Stock Option
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     Plan (the "Plan") is intended as an incentive and to encourage stock
     ownership by the non-employee directors of BancFirst Corporation (the
     "Corporation") in order to increase their proprietary interest in the
     Corporation's success.

2.   DEFINITIONS.  As used herein, the following terms shall have the
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     corresponding meanings:

     2.1.  "Committee" shall mean the Board of Directors of the Corporation, or
           a duly constituted committee of the Board consisting of three or more
           members, at least a majority of which shall be "Non-Employee
           Directors" as such term is used in Rule 16b-3 promulgated under the
           Securities Exchange Act of 1934, as amended (the "Exchange Act").

     2.2   "Common Stock" shall mean the common stock, par value $1.00 per
           share, of the Corporation.

     2.3.  "Date of Grant" shall mean the date of grant of a Stock Option
           granted hereunder as set forth in the Stock Option Agreement. In the
           event of a grant conditioned, among other things, upon stockholder
           ratification of this Plan, the date of such conditional grant shall
           be the Date of Grant for purposes of this Plan.

     2.4.  "Non-Employee Director" shall mean a person that is an elected or
           appointed member of the board of directors of a corporation, who is
           not a common-law employee of the corporation.  The determination of
           whether or not a person is a Non-Employee of the Corporation with
           respect to the grant or exercise of a Stock Option shall be made in
           accordance with the rule of Income Tax Regulation Section 1.421-7(h)
           (or successor regulation).

     2.5.  "Fair Market Value" shall mean, with respect to the exercise of an
           option under the Plan, (a) if the Common Stock is listed on a
           national securities exchange or the NASDAQ National Market System,
           the closing price of the Common Stock for the business day
           immediately preceding the day for which the determination is being
           made, or (b) if the Common Stock is not then listed on an exchange,
           the average of the closing bid and asked prices per share for the
           Common Stock in the over-the-counter market as quoted on NASDAQ for
           the business day immediately preceding the day for which the
           determination is being made, or (c) if the
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           Common Stock is not then listed on any exchange or quoted on NASDAQ,
           an amount determined in good faith by the Committee to be the fair
           market value of the Common Stock, after consideration of all relevant
           factors.

     2.6   "Nonqualified Stock Option" shall mean a Stock Option which is not
           intended to qualify for tax treatment as an "incentive stock option"
           under Section 422 of the Code.

     2.7.  "Option Exercise Price" shall mean the price paid for Shares upon the
           exercise of a Stock Option granted hereunder.

     2.8.  "Optionee" shall mean any person entitled to exercise a Stock Option
           pursuant to the terms of the Plan.

     2.9.  "Stock Option" shall mean a stock option giving an Optionee the right
           to purchase shares of the Corporation's Common Stock. Stock Options
           granted under the Plan shall be Nonqualified Stock Options.

3.   ADMINISTRATION.
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     3.1   AUTHORITY; INDEMNIFICATION. Within the limitations described herein,
           the Committee shall administer the Plan, determine the method of
           payment upon exercise of each Stock Option, determine all other terms
           of Stock Options granted hereunder and interpret, construe and
           implement the provisions of the Plan. All questions of interpretation
           of the Plan or any Stock Option granted under the Plan shall be
           determined by the Committee, and such decisions shall be binding upon
           all persons having an interest in the Plan and/or any Stock Option.
           No member of the Committee shall be liable for any action or
           determination made in good faith, and the members shall be entitled
           to indemnification and reimbursement in the manner provided in the
           Corporation's Certificate of Incorporation, or as otherwise permitted
           by law.

     3.2   RULE 16B-3 COMPLIANCE. With respect to the participation of eligible
           participants who are subject to Section 16(b) of the Exchange Act,
           the Plan shall be administered in compliance with the requirements of
           Rule 16b-3.

     3.3   SECTION 162(M) COMPLIANCE. In the event the Corporation is a
           "publicly held corporation" as defined in paragraph (2) of section
           162(m) of the Code, as amended by the Revenue Reconciliation Act of
           1993 (P.L. 103-66), and the regulations promulgated thereunder
           ("Section 162(m)"), the Corporation shall establish a committee of
           outside directors meeting the requirements of Section 162(m) to
           approve the grant of Stock Options which might reasonably be
           anticipated to result in the payment of employee remuneration that
           would

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           otherwise exceed the limit on employee remuneration deductible for
           income tax purposes pursuant to Section 162(m).

4.   ELIGIBILITY.  The individuals who shall be eligible to participate in the
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     Plan shall be such Non-Employee Directors of the Corporation, or of any
     corporation ("Subsidiary") in which the Corporation has proprietary
     interest by reason of stock ownership or otherwise, including any
     corporation in which the Corporation acquires a proprietary interest after
     the adoption of this Plan (but only if the Corporation owns, directly or
     indirectly, stock possessing not less than 50% of the total combined voting
     power of all classes of stock in the corporation), as the Committee shall
     determine from time to time.

5.   STOCK.  The stock subject to Stock Options and other provisions of the Plan
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     shall be shares of the Corporation's authorized but unissued Common Stock
     or treasury stock, as determined by the Committee. Subject to adjustment in
     accordance with the provisions of Subparagraph 6.7 hereof, the total number
     of shares of Common Stock of the Corporation on which Stock Options may be
     granted under the Plan shall not exceed in the aggregate 75,000 shares. In
     the event that any outstanding Stock Option under the Plan for any reason
     expires or is terminated prior to the end of the period during which Stock
     Options may be granted, the shares of the Common Stock allocable to the
     unexercised portion of such Stock Option may again be subject to a Stock
     Option under the Plan.

6.   TERMS AND CONDITIONS OF STOCK OPTIONS.  Stock Options granted pursuant to
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     the Plan shall be evidenced by agreements in such form as the Committee
     shall, from time to time, approve. Agreements shall comply with and be
     subject to the following terms and conditions:

     6.1   MEDIUM AND TIME OF PAYMENT. The Option Exercise Price shall be
           payable in United States Dollars upon the exercise of the Stock
           Option and may be paid in cash or by certified check, bank draft or
           money order payable to the order of the Corporation, unless otherwise
           determined by the Committee.

     6.2   NUMBER OF SHARES. Each Non-Employee Director shall be granted a Stock
           Option for 5,000 shares.

     6.3   OPTION EXERCISE PRICE. The Option Exercise Price shall be equal to
           the Fair Market Value of the Common Stock on the Date of Grant.

     6.4   TERM OF STOCK OPTIONS. Any Stock Option granted must be exercised
           within fifteen (15) years of the date of such grant.

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     6.5   DATE OF EXERCISE. Unless otherwise determined by the Committee at the
           time of granting a Stock Option, Stock Options shall be exercisable
           at the rate set forth below beginning one year from the Date of
           Grant. After becoming exercisable, the Stock Option may be exercised
           at any time and from time to time in whole or in part until
           termination of the Stock Option as set forth in Sections 6.4 or 6.6.


                                                       Cumulative
           Elapsed Years from        Percent            Percent
           Date of Grant            of Shares          of Shares
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           less than 1 year             0%                 0%
           1 to 2 years                25%                25%
           2 to 3 years                25%                50%
           3 to 4 years                25%                75%
           more than 4 years           25%               100%


     6.6   TERMINATION OF BOARD SERVICE. In the event that an Optionee's service
           on the board of directors of the Corporation shall terminate, his
           Stock Option whether or not then exercisable shall terminate
           immediately; provided, however, that if the termination is not as a
           result of embezzlement, theft or other violation of the law, the
           Optionee shall have the right to exercise his option (to the extent
           exercisable at the time of termination) at any time within 30 days
           after such termination; provided, further, that if the Optionee shall
           die while in service on the board of directors of the Corporation or
           within the period of time after termination of service during which
           he was entitled to exercise his option as hereinabove provided, his
           estate, personal representative, or beneficiary shall have the right
           to exercise his Stock Option (to the extent exercisable at the date
           of death) at any time within twelve (12) months from the date of his
           death.

     6.7   RECAPITALIZATION. The aggregate number of shares of Common Stock on
           which Stock Options may be granted to persons participating under the
           Plan, the number of shares thereof covered by each outstanding Stock
           Option, and the price per share thereof in each such Stock Option,
           shall all be proportionately adjusted for any increase or decrease in
           the number of issued shares of Common Stock of the Corporation
           resulting from a subdivision or consolidation of shares or other
           capital adjustment, or the payment of a stock dividend or other
           increase or decrease in such shares, effected without receipt of
           consideration by the Corporation; provided, however, that any
           fractional shares resulting from such adjustment shall be eliminated.
           In the event of a change in the Corporation's Common Stock which is
           limited to a change in the designation thereof to "Capital

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           Stock" or other similar designation, or a change in the par value
           thereof, or from par value to no par value, without increase in the
           number of issued shares, the shares resulting from any such change
           shall be deemed to be Common Stock within the meaning of the Plan.

     6.8   REORGANIZATION OF CORPORATION. Subject to any required action by the
           stockholders, if the Corporation shall be the surviving or resulting
           corporation in any merger or consolidation which does not result in
           change of control of the Corporation, any Stock Option granted
           hereunder shall pertain to and apply to the securities to which a
           holder of the number of shares of Common Stock subject to the Stock
           Option would have been entitled. In the event of a dissolution or
           liquidation of the Corporation or a merger or consolidation in which
           the Corporation is not the surviving or resulting corporation or
           which results in a change in control of the Corporation, or a tender
           or exchange offer which results in a change in control of the
           Corporation, the Committee shall determine: (i) whether all or any
           part of the unexercisable portion (as set forth in section 6.5) of
           any Stock Option outstanding under the Plan shall terminate; (ii)
           whether the Stock Options shall become immediately exercisable; or
           (iii) whether such Stock Options may be exchanged for options
           covering securities of any such surviving or resulting corporation,
           subject to the agreement of any such surviving or resulting
           corporation, on terms and conditions substantially similar to a Stock
           Option hereunder.

     6.9   ASSIGNABILITY. Except as provided in this Section, no Stock Option
           shall be assignable or transferable except as follows:

           (a)   by will or by the laws of descent and distribution.

           (b)   for the purpose of making a charitable gift.

           (c)   to the Optionee as trustee of a revocable trust which allows
                 the Optionee to amend or revoke the trust at any time. If the
                 Optionee relinquishes his power to amend or revoke the trust or
                 appoints a trustee other than the Optionee, the Optionee shall
                 withdraw the Stock Option from the trust prior to the
                 relinquishment of such power or appointment and revest title to
                 the Stock Option in the Optionee's individual name. If the
                 trust becomes irrevocable due to the death of the Optionee, the
                 successor trustee shall have the same power to exercise the
                 Stock Option under Section 6.6 as the personal representative.
                 If there is a successor trustee under the trust due to the
                 incapacity of the Optionee, the date of incapacity shall be
                 treated as termination of employment under Section 6.6, and the

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                 successor trustee shall have the same right to exercise the
                 option as the Optionee has under Section 6.6. The trustee or
                 any successor trustee shall be bound by all the terms and
                 conditions of the Plan and the Stock Option Agreement entered
                 into by the Plan and Optionee under this Plan.

           (d)   to the extent set forth in the Stock Option Agreement governing
                 such Stock Option.

     6.10  OPTIONEE'S AGREEMENT. If, at the time of the exercise of any Stock
           Option, it is necessary or desirable, in order to comply with any
           applicable laws or regulations relating to the sale of securities,
           that the Optionee exercising the Stock Option shall agree that he
           will purchase the shares that are subject to the Stock Option for
           investment and not with any present intention to resell the same, the
           Optionee will, upon the request of the Corporation, execute and
           deliver to the Corporation an agreement to such effect.

     6.11  RIGHTS AS A STOCKHOLDER. An Optionee shall have no rights as a
           stockholder with respect to shares covered by his Stock Option until
           the date of issuance of the shares to him and only after such shares
           are fully paid.

     6.12  OTHER PROVISIONS. The option agreements authorized under the Plan may
           contain such other provisions as the Committee shall deem advisable.

7.   MARKETABILITY OF SHARES. The Common Stock is currently traded on the NASDAQ
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     National Market System. As a result, its liquidity varies widely in
     response to supply and demand. Consequently, the Corporation can give no
     assurances as to the marketability of shares acquired under the Plan.

8.   TAX IMPLICATIONS.  It is anticipated that Stock Options granted under the
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     Plan will be treated as Nonqualified Stock Options by the Internal Revenue
     Service. As such, exercise of the Stock Option would generate a taxable
     event with the difference between the original Option Exercise Price and
     the Fair Market Value of the Common Stock at the time of exercise being
     treated as ordinary income.

9.   TERM OF PLAN.  No Stock Option may be granted after December 31, 2014.
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10.  NO OBLIGATION TO EXERCISE OPTION.  The granting of a Stock Option shall
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     impose no obligation upon the Optionee to exercise such Stock Option.

11.  AMENDMENTS.  The Board of Directors may from time to time amend, alter,
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     suspend, or discontinue the Plan or alter or amend (including decrease of
     the Option Exercise Price

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     by cancellation and substitution of options or otherwise) any and all
     option agreements granted thereunder; provided, however, that no such
     action of the Board of Directors may, without approval of the stockholders
     of the Corporation, alter the provisions of the Plan so as to (a)
     materially increase the benefits accruing to participants under the Plan;
     (b) materially increase the number of securities which may be issued under
     the Plan; or (c) materially modify the requirements as to eligibility for
     participation in the Plan; and provided, further, that no amendment may,
     without the consent of the Optionee, affect any then outstanding Stock
     Options or unexercised portions thereof. In addition, the approval of the
     Corporation's stockholders shall be sought for any amendment to the Plan or
     a Stock Option for which the Committee deems stockholder approval necessary
     in order to comply with Rule 16b-3.

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