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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                   FORM 12b-25     Commission File Number 1-8032

                           NOTIFICATION OF LATE FILING

(CHECK ONE):  [X] Form 10-K   [ ] Form 20-F   [ ] Form 11-K   [ ] Form 10-Q
              [ ] Form N-SAR

              For Period Ended: December 31, 1999
              [ ] Transition Report on Form 10-K
              [ ] Transition Report on Form 20-F
              [ ] Transition Report on Form 11-K
              [ ] Transition Report on Form 10-Q
              [ ] Transition Report on Form N-SAR
              For the Transition Period Ended:
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  READ ATTACHED INSTRUCTION SHEET BEFORE PREPARING FORM. PLEASE PRINT OR TYPE.
    NOTHING IN THIS FORM SHALL BE CONSTRUED TO IMPLY THAT THE COMMISSION HAS
                   VERIFIED ANY INFORMATION CONTAINED HEREIN.
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If the notification relates to a portion of the filing checked above, identify
the Item(s) to which the notification relates:

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PART I -- REGISTRANT INFORMATION

    San Juan Basin Royalty Trust
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Full Name of Registrant

    N/A
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Former Name if Applicable

    Bank One Texas, N.A., Corporate Trust Department, P.O. Box 2604
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Address of Principal Executive Office (Street and Number)

    Fort Worth, Texas 76113
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City, State and Zip Code


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PART II -- RULES 12b-25(b) AND (c)

If the subject report could not be filed without unreasonable effort or expense
and the registrant seeks relief pursuant to Rule 12b-25(b), the following should
be completed. (Check box if appropriate)

      (a) The reasons described in reasonable detail in Part III of this form
          could not be eliminated without unreasonable effort or expense;

[X]   (b) The subject annual report, semi-annual report, transition report on
          Form 10-K, Form 20-F, 11-K or Form N-SAR, or portion thereof, will be
          filed on or before the fifteenth calendar day following the prescribed
          due date; or the subject quarterly report of transition report on Form
          10-Q, or portion thereof will be filed on or before the fifth calendar
          day following the prescribed due date; and

      (c) The accountant's statement or other exhibit required by Rule 12b-25(c)
          has been attached if applicable.

PART III -- NARRATIVE

State below in reasonable detail the reasons why Forms 10-K, 20-F, 11-K, 10-Q,
N-SAR, or the transition report or portion thereof, could not be filed within
the prescribed time period. (ATTACH EXTRA SHEETS IF NEEDED)

The registrant could not file the referenced 10-K without unreasonable effort or
expense because the office building of the Trustee of the registrant was damaged
due to a tornado that passed through the city of Fort Worth on Tuesday, March
28, 2000. In addition, the facilities of the public relations company
contracting for preparation of the annual report of the registrant were also
damaged by the tornado. As a result, neither the Trustee nor the public
relations company employees were able to enter their respective places of
business in order to complete the annual report of the registrant.

PART IV -- OTHER INFORMATION

(1)   Name and telephone number of person to contact in regard to this
      notification.

            Lee Ann Anderson           817                       884-4630
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               (Name)               (Area Code)             (Telephone Number)

(2)   Have all other periodic reports required under Section 13 or 15(d) of the
      Securities Exchange Act of 1934 or Section 30 of the Investment Company
      Act of 1940 during the preceding 12 months or for such shorter period that
      the registrant was required to file such report(s) has been filed? If the
      answer is no, identify report(s).

                                                            [X] Yes   [ ] No

(3)   Is it anticipated that any significant change in results of operations
      from the corresponding period for the last fiscal year will be reflected
      by the earnings statements to be included in the subject report or portion
      thereof?

                                                            [ ] Yes   [X] No

      If so, attach an explanation of the anticipated change, both narratively
      and quantitatively, and, if appropriate, state the reasons why a
      reasonable estimate of the results cannot be made.


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                          San Juan Basin Royalty Trust
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                   Name of Registrant as Specified in Charter

      has caused this notification to be signed on its behalf by the undersigned
      hereunto duly authorized.

                                     BANK ONE, TEXAS, N.A.
                                     TRUSTEE OF THE SAN JUAN
                                     BASIN ROYALTY TRUST


     Date:  March 30, 2000           By:     /s/ Lee Ann Anderson
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                                            Lee Ann Anderson
                                            Vice President

INSTRUCTION: The form may be signed by an executive officer of the registrant or
by any other duly authorized representative. The name and title of the person
signing the form shall be typed or printed beneath the signature. If the
statement is signed on behalf of the registrant by an authorized representative
(other than an executive officer), evidence of the representative's authority to
sign on behalf of the registrant shall be filed with the form.

                                    ATTENTION
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   INTENTIONAL MISSTATEMENTS OR OMISSIONS OF FACT CONSTITUTE FEDERAL CRIMINAL
                        VIOLATIONS (SEE 18 U.S.C. 1001).

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                              GENERAL INSTRUCTIONS

1.    This form is required by Rule 12b-25 (17 CFR 240, 12b-25) of the General
      Rules and Regulations under the Securities Exchange Act of 1934.

2.    One signed original and four conformed copies of this form and amendments
      thereto must be completed and filed with the Securities and Exchange
      Commission, Washington, D.C. 20549, in accordance with Rule 0-3 of the
      General Rules and Regulations under the Act. The information contained in
      or filed with the form will be made a matter of public record in the
      Commission files.

3.    A manually signed copy of the form and amendments thereto shall be filed
      with each national securities exchange on which any class of securities of
      the registrant is registered.

4.    Amendments to the notifications must also be filed on form 12b-25 but need
      not restate information that has been correctly furnished. The form shall
      be clearly identified as an amended notification.

5.    ELECTRONIC FILERS. This form shall not be used by electronic filers unable
      to timely file a report solely due to electronic difficulties. Filers
      unable to submit a report within the time period prescribed due to
      difficulties in electronic filing should comply with either Rule 201 or
      Rule 202 of Regulation S-T (Section 232.201 or Section 232.202 of this
      chapter) or apply for an adjustment in filing date pursuant to Rule 13(b)
      of Regulation S-T (Section 232.13(b) of this chapter).