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                                  Exhibit 10.5

                         The NB&T Financial Group, Inc.

                     Supplemental Executive Retirement Plan

                             PARTICIPATION AGREEMENT

     THIS PARTICIPATION AGREEMENT (the "Participation Agreement") is entered
into as of this 19th day of November, 2002, by and between the NB&T Financial
Group, Inc. (the "Sponsor"), The National Bank and Trust Company (the
"Employer") and CHARLES L. DEHNER an executive of the Employer (the
"Participant").

RECITALS:

     WHEREAS, the Employer has adopted the ("Plan") effective as of August 20,
2002, and the Administrator has determined that the Participant shall be
eligible to participate in the Plan on the terms and conditions set forth in
this Participation Agreement and the Plan;

     NOW, THEREFORE, in consideration of the foregoing and the agreements and
covenants set forth herein, the parties agree as follows:

          1. Definitions. Except as otherwise provided, or unless the context
     otherwise requires, the terms used in this Participation Agreement shall
     have the same meanings as set forth in the Plan.

          2. Incorporation of Plan. The Plan, a copy of which is attached hereto
     as Exhibit A, is hereby incorporated into this Participation Agreement as
     if fully set forth herein, and the parties hereby agree to be bound by all
     of the terms and provisions contained in the Plan. The Participant hereby
     acknowledges receipt of a copy of the Plan and confirms his understanding
     and acceptance of all of the terms and conditions contained therein.

          3. Effective Date of Participation. The effective date of the
     Participant's participation in the Plan shall be November 19, 2002 (the
     "Participation Date").

          4. Normal Retirement Age. The Participant's Normal Retirement Age for
     purposes of the Plan and this Participation Agreement is age fifty-five
     (55).

          5. Prohibition Against Funding. Should any investment be acquired in
     connection with the liabilities assumed under this Plan and Participation
     Agreement, it is expressly understood and agreed that the Participants and
     Beneficiaries shall not have any right with respect to, or claim against,
     such assets nor shall any such purchase be construed to create a trust of
     any kind or a fiduciary relationship between the Employer and the
     Participants, their Beneficiaries or any other person. Any such assets
     shall be and remain a part of the general, unpledged, unrestricted assets
     of the Employer, subject to the claims of its general creditors. It is the
     express intention of the parties hereto that this arrangement shall be
     unfunded for tax purposes and for purposes of Title I of ERISA. The
     Participant shall be required to look to the provisions of the Plan and to
     the Employer itself for enforcement of any and all benefits due under this
     Participation Agreement and, to the extent the Participant acquires a right
     to receive payment under the Plan and this Participation Agreement, such
     right shall be no greater than the right of any unsecured general creditor
     of the Employer. The Employer shall be designated the owner and beneficiary
     of any investment acquired in connection with its obligation under the Plan
     and this Participation Agreement.

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          6.   Provisions Related to SERP Benefit.

          (a)  Benefit. In the event the Participant has attained fifty-five
               (55) years of age, on or prior to, the Participant's effective
               date of Termination, such Participant shall be entitled to four
               annual SERP Benefit payments of twenty five thousand dollars
               ($25,000).

                    Vesting. There will be no partial Vesting available to the
               Participant. The Participant shall become 100% vested in the SERP
               Benefit upon the occurrence of:

                    (1)  Normal Retirement; or

                    (2)  Change in Control.

                    Effect of Termination for Cause. A Participant who is
               Terminated for Cause before his or her Termination will receive
               no SERP Benefit under this Plan. A Participant who is Terminated
               for Cause at or after his Normal Retirement Date will be entitled
               to the amount described in Section 6(a) of this Participation.

                    Effect of Change in Control. (i) If a Change in Control
               occurs before the Participant Terminates and before the
               Participant reaches age fifty-five (55), he will be entitled to
               receive [beginning at age fifty-five (55)] the benefit described
               in Section 6(a) of this Participation Agreement as if he had been
               age fifty-five (55) on the date of the Change in Control. This
               amount will be paid as provided in Section 6(b) of this
               Participation Agreement, applied as of the date the Participant
               reaches age fifty-five (55). (ii) If a Change in Control occurs
               before the Participant Terminates but after the Participant
               reaches age fifty-five (55) he will be entitled to the benefit
               described in Section 6(a) of this Participation. This amount will
               be paid as provided in Section 6(b) of this Participation
               Agreement, applied as of the date the Participant Terminates.

                    Effect of Parachute Excise Taxes. If the sum of the payments
               provided in the preceding subsection and those provided under any
               other plan, program or agreement between the Participant and any
               Related Entity member constitute "excess parachute payments" as
               defined in Code (S) 280G(b)(1), the Sponsor will reduce (or cause
               the Employer to reduce) the Participant's SERP Benefits so that
               his total "parachute payment" as defined in Code (S)
               280G(b)(2)(A) under this and any all other agreements will be
               $1.00 less than the amount that would be an "excess parachute
               payment."

          (b)  Form of SERP Benefit Payment. The SERP Benefit will be paid
               annually for a period of four (4) years beginning on the first
               business day of the first calendar month of the first calendar
               year that begins after the Participant Terminates.

          (c)  Post Termination Death Benefit. Participant's SERP Benefit shall
               be payable to the Participant in annual installments for four (4)
               years. In the event the Participant should die after payments
               have commenced but before the fourth (4th) annual payment has
               been made, the Participant's Beneficiary, as designated pursuant
               to this Participation Agreement, shall be paid the balance of the
               remaining annual SERP Benefit payments that would have been made
               to the Participant had he lived, in equal annual installments.
               Payments will cease upon the earlier of the Beneficiary's death
               or payment of the fourth (4th) payment (determined by aggregating
               all annual payments made to the Participant before his death and
               those made to the Beneficiary after the Participant's death). No
               SERP Benefits will be paid to any beneficiary of a Beneficiary.

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          (d)  Post-Normal Retirement (but Pre Termination) Death Benefit. In
               the event the Participant dies prior to his Termination of
               service but after attaining Normal Retirement Age, the
               Participant's Beneficiary shall receive the SERP Benefit in
               effect at the time of the Participant's death.

          (e)  Pre Termination Death Benefit. In the event the Participant dies
               prior to his Termination but before attaining Normal Retirement
               Age, the Participant's Beneficiary shall receive a SERP Benefit
               calculated as if the Participant had reached age fifty-five (55)
               on the day preceding his death.

     7.   Participant's Covenants.

          (a)  Covenant Not to Compete. Commencing on the date of Participant's
               Termination with the Employer and all Affiliates (hereinafter
               defined) and ending on the third anniversary thereof (the
               "Restricted Competition Period"), Participant agrees that he
               shall not, and shall not permit any of his Affiliates, alone,
               together or in association with others, either as principal,
               agent, owner, shareholder, officer, director, partner, lender,
               investor, independent contractor, consultant or in any other
               capacity, to engage in, have a financial interest in or be in any
               way connected or affiliated with, or render advice or services to
               any natural person, organization or entity of any type that
               engages in any activity which would compete, in any way, in any
               county in which a Related Entity has a branch or business
               operation at the time of Participant's Termination of employment,
               with the business operated by any Related Entity or conducting
               the business of banking and providing other financial services.
               For purposes of this subsection, an "Affiliate" of a person shall
               mean (i) any natural person, organization or entity of any type
               that directly, or indirectly through one or more intermediaries,
               controls, is controlled by or is under common control with, such
               specified person; (ii) any relative or spouse of such person, or
               any relative of such spouse, any one of whom has the same home as
               such person; (iii) any trust or estate in which such person or
               any of the persons specified in (ii) collectively own ten percent
               or more of the total beneficial interest or of which any of such
               persons serve as trustee, executor or in any similar capacity; or
               (iv) any corporation or other organization in which such person
               or any of the persons specified in (ii) are the beneficial owners
               collectively of ten percent or more of any class of equity
               securities or ten percent or more of the equity interest. For
               purposes of the definition of the term "Affiliate," "control"
               means the power to direct the management and policies of such
               person, directly or indirectly, whether through the ownership of
               voting securities, by contract or otherwise.

                    The Participant and each Related Entity agree that the value
               to them of this Covenant Not to Compete is equal to three hundred
               percent of the annualized gross compensation due to the
               Participant at his rate of compensation as in effect immediately
               before his Termination and that this amount has been included in
               the SERP Benefit.

          (b)  Covenant Not to Solicit. During the Restricted Competition Period
               [defined in Section 7(a)], Participant further agrees that he
               will not, and will not permit any Affiliate [defined in Section
               7(a)], directly or indirectly, to solicit, divert, take away or
               interfere with, or attempt to solicit, divert, take away or
               interfere with, the relationship of any Related Entity with any
               person who is or was a customer, employee or supplier of any
               Related Entity at any time during the period commencing two years
               immediately prior to the date of this Participation Agreement and
               ending upon the Participant's Termination.

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                    The Participant and each Related Entity agree that the value
               to them of this Covenant Not to Solicit is equal to two hundred
               percent of the annualized gross compensation due to the
               Participant at his rate of compensation as in effect immediately
               before his Termination and that this amount has been included in
               the SERP Benefit.

          (c)  Interpretation of Covenants. The parties to this Participation
               Agreement acknowledge and agree that the duration and area for
               which the Covenant Not to Compete and the Covenant Not to Solicit
               are to be effective are fair and reasonable and are reasonably
               required for the protection of the business of the Related
               Entities. In the event that any court or arbitrator determines
               that the time period or the area, or both of them, are
               unreasonable as to any covenant and that such covenant is to that
               extent unenforceable, the parties hereto agree that the covenant
               shall remain in full force and effect for the greatest time
               period and in the greatest area that would not render it
               unenforceable. The parties intend that each covenant shall be
               deemed to be a series of separate covenants, one for each and
               every county of each and every state of the United States of
               America and one for each and every political subdivision of each
               and every other country in which the Covenant Not to compete or
               other covenant is intended to be effective and is not proscribed
               by law.

     8. Beneficiary. Notwithstanding the definition of "Beneficiary" set forth
in the Plan, Beneficiary means the person to whom the Participant is legally
married on the date this Participation Agreement is signed ("Spouse"). If the
Participant's Spouse dies while the Participant is alive, no benefit will be
paid after the Participant's death whether or not the Participant subsequently
remarries and no person claiming through the Spouse or Participant will have any
rights under this Plan. Also, no benefits will be due to any beneficiary of a
Beneficiary.

IN WITNESS WHEREOF, each of the parties has caused this Participation Agreement
to be executed as of the day first above written.

                                            NB&T FINANCIAL GROUP, INC.


                                            By:
                                               ---------------------------------

                                            Title:
                                                  ------------------------------


PARTICIPANT:                                THE NATIONAL BANK AND TRUST COMPANY


Charles L. Dehner                           By:
-----------------------------------------      ---------------------------------
[Name of Participant]

                                            Title:
-----------------------------------------         ------------------------------
Signature of Participant


ATTESTED:                                   ATTESTED:


By:                                         By:
   --------------------------------------      ---------------------------------

Title:                                      Title:
      -----------------------------------         ------------------------------

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