EXHIBIT 13

ANNUAL REPORT TO SHAREHOLDERS

[COVER PAGE]

[PERMIAN BASIN ROYALTY TRUST LOGO]

PERMIAN BASIN ROYALTY TRUST ANNUAL REPORT & FORM 10-K 2005

[MAP OF COUNTIES IN TEXAS]

TEXAS ROYALTY PROPERTIES ARE LOCATED IN 35 TEXAS COUNTIES.
WADDELL RANCH PROPERTIES ARE LOCATED IN CRANE COUNTY.

The Trust

     The Permian Basin Royalty Trust’s (the “Trust”) principal assets are comprised of a 75% net overriding royalty interest carved out by Southland Royalty Company (“Southland”) from its fee mineral interest in the Waddell Ranch properties in Crane County, Texas (“Waddell Ranch properties”), and a 95% net overriding royalty interest carved out by Southland from its major producing royalty properties in Texas (“Texas Royalty properties”). The interests out of which the Trust’s net overriding royalty interests were carved were in all cases less than 100%. The Trust’s net overriding royalty interests represent burdens against the properties in favor of the Trust without regard to ownership of the properties from which the overriding royalty interests were carved. The net overriding royalties above are collectively referred to as the “Royalties.” The properties and interests from which the Royalties were carved and which the Royalties now burden are collectively referred to as the “Underlying Properties.”

     The Trust has been advised that effective January 1, 1996, Southland was merged with and into Meridian Oil Inc. (“Meridian”), a Delaware corporation, with Meridian being the surviving corporation. Meridian succeeded to the ownership of all the assets, has the rights, powers, and privileges, and assumed all of the liabilities and obligations of Southland. Effective July 11, 1996, Meridian changed its name to Burlington Resources Oil & Gas Company, now Burlington Resources Oil & Gas Company LP (“BROG”). Any reference to BROG hereafter for periods prior to the occurrence of the aforementioned name change or merger should, as applicable, be construed to be a reference to Meridian or Southland. Further, BROG notified the Trust that, on February 14, 1997, the Texas Royalty properties that are subject to the Net Overriding Royalty Conveyance dated November 1, 1980 (“Texas Royalty Conveyance”), were sold to Riverhill Energy Corporation (“Riverhill Energy”) of Midland, Texas. On December 12, 2005, BRI and ConocoPhillips announced a proposed transaction pursuant to which ConocoPhillips would acquire BRI, subject to shareholder approval by BRI.

Units of Beneficial Interest

     Units of Beneficial Interest (“Units”) of the Trust are traded on the New York Stock Exchange with the symbol PBT. Quarterly high and low sales prices and the aggregate amount of monthly distributions paid each quarter during the Trust’s two most recent years were as follows:

     Approximately 1,581 Unit holders of record held the 46,608,796 Units of the Trust at December 31, 2005.

     The Trust has no equity compensation plans and has not repurchased any Units during the period covered by this report.

To Unit Holders

     We are pleased to present the twenty-fifth Annual Report of the Trust. The report includes a copy of the Trust’s Annual Report on Form 10-K to the Securities and Exchange Commission for the year ended December 31, 2005, without exhibits. Both the report and accompanying Form 10-K contain important information concerning the Trust’s properties, including the oil and gas reserves attributable to the Royalties owned by the Trust. Production figures, drilling activity and certain other information included in this report have been provided to the Trust by BROG (formerly Meridian and Southland) and Riverhill.

     As more particularly explained in the Notes to the Financial Statements appearing in this report and in Item 1 of the accompanying Form 10-K, Bank of America, N.A., as Trustee, has the primary function under the Trust Indenture of collecting the monthly net proceeds attributable to the Royalties and making monthly distributions to the Unit holders, after deducting Trust administrative expenses and any amounts necessary for cash reserves.

     Royalty income received by the Trustee for the year ended December 31, 2005, was $62,967,150 and interest income earned for the same period was $63,909. General and administrative expenses amounted to $763,390. A total of $62,267,669 or 1.335964 per Unit, was distributed to Unit holders during 2005. A discussion of factors affecting the distributions for 2005 may be found in the Trustee’s Discussion and Analysis section of this report and the accompanying Form 10-K.

     As of December 31, 2005, the Trust’s proved reserves were estimated at 6,850,000 Bbls of oil and 26,532,000 Mcf of gas. The estimated future net revenues from

proved reserves at December 31, 2005 amount to $518,074,000 or $11.12 per Unit. The present value of estimated future net revenues discounted at 10% at December 31, 2005 was $293,351,000 or $6.08 per Unit. The computation of future net revenues is made following guidelines prescribed by the Financial Accounting Standards Board (explained in Item 2 of the accompanying Form 10-K) based on year-end prices and costs.

     As has been previously reported, Southland advised the Trust that it became operator of record of the Waddell Ranch properties on May 1, 1991. Meridian, as successor by merger, became the operator of record effective January 1, 1996. Meridian changed its name to Burlington Resources Oil & Gas Company in 1996 and again to Burlington Resources Oil & Gas Company LP in 2000. All field, technical and accounting operations, however, have been carried out by Schlumberger Technology Corporation (“STC”) under the direction of BROG, and by Riverhill Capital Corporation (“Riverhill Capital”).

     As was previously reported, in February 1997, BROG sold its interest in the Texas Royalty properties that are subject to the Texas Royalty Conveyance to Riverhill Energy, which at the time was a wholly-owned subsidiary of Riverhill Capital and an affiliate of CMC. Subsequently, the Trustee was advised that STC acquired all of the shares of Riverhill Capital. The Trustee has been advised that, as part of this transaction, ownership of Riverhill Energy’s interests in the Texas Royalty properties referenced above remain in Riverhill Energy, which was owned by the former shareholders of Riverhill Capital. Riverhill will continue to perform all accounting operations pertaining to the Texas Royalty properties.

     Percentage depletion is allowed on proven properties acquired after October 11, 1990. For Units acquired after such date, Unit holders would normally compute both percentage depletion and cost depletion from each property, and claim the larger amount as a deduction on their income tax returns. The Trustee and its accountants have estimated the cost depletion for January through December 2005, and it appears that percentage depletion will exceed cost depletion for all Unit holders.

     Royalty income is generally considered portfolio income under the passive loss rules. Therefore, in general, it appears that Unit holders should not consider the taxable income from the Trust to be passive income in determining net passive income or loss. Unit holders should consult their tax advisors for further information.

     Unit holders of record will continue to receive an individualized tax information letter for each of the quarters ending March 31, June 30 and September 30, 2006, and for the year ending December 31, 2006. Unit holders owning Units in nominee name may obtain monthly tax information from the Trustee upon request.

Description of the Properties

     The net overriding royalty interests held by the Trust are carved out of high-quality producing oil and gas properties located primarily in West Texas. A production index for oil and gas properties is the number of years derived by dividing remaining reserves by current production. The production index for the Trust properties based on the reserve report prepared by independent petroleum engineers as of December 31, 2005, is approximately 9 years.

     The net profits/overriding royalty interest in the Waddell Ranch properties is the largest asset of the Trust. The mineral interests in the Waddell Ranch, from which such net royalty interests are carved vary from 37.5% (Trust net interest) to 50% (Trust net interest) in 76,922 gross acres and 33,246 net acres, containing 782 gross (349 net) productive oil wells, 193 gross (81 net) productive gas wells and 316 gross (137 net) injection wells.

     Six major fields on the Waddell Ranch properties account for more than 90% of the total production. In the six fields, there are 12 producing zones ranging in depth from 2,800 to 10,600 feet. Most prolific of these zones are the Grayburg and San Andres, which produce from depths between 2,800 and 3,400 feet. Productive from the San Andres are the Sand Hills (Judkins) gas field and the Sand Hills (McKnight) oil field, the Dune (Grayburg/San Andreas) oil field, and the Waddell (Grayburg/San Andreas) oil field.

     The Dune and Waddell oil fields are productive from both the Grayburg and San Andres formations. The Sand Hills (Tubb) oil fields produce from the Tubb formation at depths averaging 4,300 feet, and the University Waddell (Devonian) oil field is productive from the Devonian formation between 8,400 and 9,200 feet.

     All of the major oil fields on the Waddell Ranch properties are currently being water flooded. Engineering studies and 3-D seismic evaluations on these fields indicate the potential for increased production through infill drilling, modifications of existing water flood techniques, installation of larger capacity pumping equipment. Capital expenditures for remedial and maintenance activities during 2005 totaled approximately $14.7 million.

     The Texas Royalty properties, out of which the other net overriding royalty was carved, are located in 33 counties across Texas. The Texas Royalty properties consist of approximately 125 separate royalty interests containing approximately 303,000 gross (51,000 net) producing acres. Approximately 41% of the future net revenues discounted at 10% attributable to Texas Royalty properties are located in the Wasson and Yates fields.

     BROG has informed the Trustee that the 2006 capital expenditures budget with regard to the Waddell Ranch properties should total approximately $30.3 million gross of which $14.3 million gross is attributable to drilling, $15 million gross to workovers and recompletions, and $1 million gross to facilities.

Computation of Royalty Income Received by the Trust

     The Trust’s royalty income is computed as a percentage of the net profit from the operation of the properties in which the Trust owns net overriding royalty interests. The percentages of net profits are 75% and 95% in the cases of the Waddell Ranch properties and the Texas Royalty properties, respectively. Royalty income received by the Trust for the five years ended December 31, 2005, was computed as shown in the table on the next page.

Discussion and Analysis

Trustee’s Discussion and Analysis for the Three-Year Period Ended December 31, 2005

Critical Accounting Policies and Estimates

     The trust’s financial statements reflect the selection and application of accounting policies that require the Trust to make significant estimates and assumptions. The following are some of the more critical judgment areas in the application of accounting policies that currently affect the Trust’s financial condition and results of operations.

     Revenues from Royalty Interests are recognized in the period in which amounts are received by the Trust. Royalty income received by the Trust in a given calendar year will generally reflect the proceeds from natural gas produced for the twelve-month period ended October 31^st in that calendar year.

     Independent petroleum engineers estimate the net proved reserves attributable to the Royalty Interests. In accordance with Statement of Financial Standards No. 69, “Disclosures About Oil and Gas Producing Activities,” estimates of future net revenues from proved reserves have been prepared using year-end contractual gas prices. The reserves actually recovered and the timing of production may be substantially different from the reserve estimates and related costs. Numerous uncertainties are inherent in estimating volumes and the value of proved reserves and in projecting future production rates and the timing of development of non-producing reserves. Such reserve estimates are subject to change as market conditions change.

     Detailed information concerning the number of wells on royalty properties is not generally available to the owner of royalty interests. Consequently, the Registrant does not have information that would be disclosed by a company with oil and gas operations, such as an accurate account of the number of wells located on its royalty properties, the number of exploratory or development wells drilled on its royalty properties during the periods presented by this report, or the number of wells in process or other present activities on its royalty properties, and the Registrant cannot readily obtain such information.

     Contingencies related to the Underlying Properties that are unfavorably resolved would generally be reflected by the Trust as reductions to future royalty income payments to the Trust with corresponding reductions to cash distributions to Unit holders.

Liquidity and Capital Resources

     As stipulated in the Trust Agreement, the Trust is intended to be passive in nature and the Trustee does not have any control over or any responsibility relating to the operation of the Underlying Properties. The Trustee has powers to collect and distribute proceeds received by the Trust and pay Trust liabilities and expenses and its actions have been limited to those activities. The Trust is a passive entity and other than the Trust’s ability to periodically borrow money as necessary to pay expenses, liabilities and obligations of the Trust that cannot be paid out of cash held by the Trust, the Trust is prohibited from engaging in borrowing transactions. As a result, other than such borrowings, if any, the Trust has no source of liquidity or capital resources other than the Royalties.

Results of Operations

     Royalty income received by the Trust for the three-year period ended December 31, 2005, is reported in the following table:

     Royalty income of the Trust for the calendar year is associated with actual oil and gas production for the period November of the prior year through October of the current year. Oil and gas sales for 2005, 2004 and 2003 for the Royalties and the Underlying Properties, excluding portions attributable to the adjustments discussed hereafter, are presented in the following table:

     The average price of oil increased to $48.77 per barrel in 2005, up from $36.30 per barrel in 2004. In addition, the average price of gas increased from $5.47 per Mcf in 2004 to $6.94 per Mcf in 2005.

     Since the oil and gas sales attributable to the Royalties are based on an allocation formula that is dependent on such factors as price and cost (including capital expenditures), production amounts do not necessarily provide a meaningful comparison. Total oil production increased approximately 6% from 2004 to 2005 primarily due to higher oil prices compared to previous years. Total gas production increased approximately 11% from 2004 to 2005 primarily due to an increase in capital expenditures for gas wells.

     Total capital expenditures in 2005 used in the net overriding royalty calculation were approximately $7.2 million compared to $6.5 million in 2004 and $7.7 million in 2003. During 2005, there were 6 gross (3 net) wells drilled and completed on the Waddell Ranch properties. At December 31, 2005, there were no wells in progress on the Waddell Ranch properties.

     In 2005, lease operating expense and property taxes on the Waddell Ranch properties amounted to approximately $12.2 million, which amount was higher than 2004 by $2.8 million.

     The Trustee has been advised by BROG that for the period August 1, 1993, through January 1, 2006, the oil from the Waddell Ranch was and will be sold under a competitive bid to a third party.

     During 2005, the monthly royalty receipts were invested by the Trustee in U.S. Treasury securities until the monthly distribution date, and earned interest totaled $63,909. Interest income for 2004 and 2003 was $ 19,883 and $13,937, respectively.

     General and administrative expenses in 2005 were $763,390 compared to $489,810 in 2004 and $496,890 in 2003.

     Distributable income for 2005 was $62,267,669, or $1.335964 per Unit.

     Distributable income for 2004 was $44,546,743, or $.955758 per Unit.

     Distributable income for 2003 was $32,113,125, or $.688993 per Unit.

Results of the Fourth Quarters of 2005 and 2004

     Royalty income received by the Trust for the fourth quarter of 2005 amounted to $20,700,741 or $.444138 per Unit. For the fourth quarter of 2004, the Trust received royalty income of $15,117,305 or $.367255 per Unit. Interest income for the fourth quarter of 2005 amounted to $27,098 compared to $9,045 for the fourth quarter of 2004. The increase in interest income can be attributed primarily to an increase in funds available for investment and an increase in interest rate. General and administrative expenses totaled $115,154 for the fourth quarter of 2005 compared to $76,881 for the fourth quarter of 2004.

     Royalty income for the Trust for the fourth quarter is associated with actual oil and gas production during August through October from the Underlying Properties. Oil and gas sales attributable to the Royalties and the Underlying Properties for the quarter and the comparable period for 2004 are as follows:

     The posted price of oil increased for the fourth quarter of 2005 compared to the fourth quarter of 2004, resulting in an average price per barrel of $58.88 compared to $43.87 in the same period of 2004. The average price of gas increased for the fourth quarter of 2005 compared to the same period in 2004, resulting in an average price per Mcf of $8.70 compared to $6.18 in the fourth quarter of 2004.

     The Trustee has been advised that oil sales increased in 2005 compared to the same period in 2004 primarily due to higher capital expenditures in 2005 offsetting natural production declines. Gas sales from the Underlying Properties increased in the fourth quarter of 2005 compared to the same period in 2004 due to the same factors.

     The Trust has been advised that no well was drilled and completed during the three months ended December 31, 2005, and there were no wells in progress.

Off-Balance Sheet Arrangements.

     As stipulated in the Trust Agreement, the Trust is intended to be passive in nature and the Trustee does not have any control over or any responsibility relating to the operation of the Underlying Properties. The Trustee has powers to collect and distribute proceeds received by the Trust and pay Trust liabilities and expenses and its actions have been limited to those activities. Therefore, the Trust has not engaged in any off-balance sheet arrangements.

Tabular Disclosure of Contractual Obligations.

PERMIAN BASIN ROYALTY TRUST
FINANCIAL STATEMENTS

STATEMENTS OF ASSETS, LIABILITIES AND TRUST CORPUS
DECEMBER 31, 2005 AND 2004

STATEMENTS OF DISTRIBUTABLE INCOME
FOR THE THREE YEARS ENDED DECEMBER 31, 2005

STATEMENTS OF CHANGES IN TRUST CORPUS
FOR THE THREE YEARS ENDED DECEMBER 31, 2005

The accompanying notes to financial statements are an integral part of these statements.

NOTES TO FINANCIAL STATEMENTS

1. Trust Organization and Provisions

     The Permian Basin Royalty Trust (“Trust”) was established as of November 1, 1980. Bank of America, N.A. (“Trustee”) is Trustee for the Trust. Southland Royalty Company (“Southland”) conveyed to the Trust (1) a 75% net overriding royalty in Southland’s fee mineral interest in the Waddell Ranch in Crane County, Texas (“Waddell Ranch properties”) and (2) a 95% net overriding royalty carved out of Southland’s major producing royalty properties in Texas (“Texas Royalty properties”). The net overriding royalties above are collectively referred to as the “Royalties.”

     On November 3, 1980, Units of Beneficial Interest (“Units”) in the Trust were distributed to the Trustee for the benefit of Southland shareholders of record as of November 3, 1980, who received one Unit in the Trust for each share of Southland common stock held. The Units are traded on the New York Stock Exchange.

     The terms of the Trust Indenture provide, among other things, that:

2. Net Overriding Royalty Interests and Distribution to Unit Holders

     The amounts to be distributed to Unit holders (“Monthly Distribution Amounts”) are determined on a monthly basis. The Monthly Distribution Amount is an amount equal to the sum of cash received by the Trustee during a calendar month attributable to the Royalties, any reduction in cash reserves and any other cash receipts of the Trust, including interest, reduced by the sum of liabilities paid and any increase in cash reserves. If the Monthly Distribution Amount for any monthly period is a negative number, then the distribution will be zero for such month. To the extent the distribution amount is a negative number, that amount will be carried forward and deducted from future monthly distributions until the cumulative distribution calculation becomes a positive number, at which time a distribution will be made. Unit holders of record will be entitled to receive the calculated Monthly Distribution Amount for each month on or

before 10 business days after the monthly record date, which is generally the last business day of each calendar month.

     The cash received by the Trustee consists of the amounts received by owners of the interest burdened by the Royalties from the sale of production less the sum of applicable taxes, accrued production costs, development and drilling costs, operating charges and other costs and deductions, multiplied by 75% in the case of the Waddell Ranch properties and 95% in the case of the Texas Royalty properties.

     The initial carrying value of the Royalties ($10,975,216) represented Southland’s historical net book value at the date of the transfer to the Trust. Accumulated amortization as of December 31, 2005 and 2004, aggregated $9,364,586 and $9,179,949, respectively.

3. Basis of Accounting

     The financial statements of the Trust are prepared on the following basis:

     The financial statements of the Trust differ from financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) because revenues are not accrued in the month of production and certain cash reserves may be established for contingencies which would not be accrued in financial statements prepared in accordance with GAAP. Amortization of the Royalties calculated on a unit-of-production basis is charged directly to trust corpus. This comprehensive basis of accounting other than GAAP corresponds to the accounting permitted for royalty trusts by the U.S. Securities and Exchange Commission as specified by Staff Accounting Bulletin Topic 12:E, Financial Statements of Royalty Trusts.

4. New Accounting Pronouncements

     SFAS No. 123R “Accounting for Stock-Based Compensation” was issued in December 2004 and provides new implementation guidance for stock-based compensation accounting. This Statement is effective for public entities that do not file as small business issuers-as of the beginning of the first interim or annual reporting period that begins after June 15, 2005. The Trust has no options or other stock-based instruments and accordingly, the impact of this new Standard will not be material to the financial statements of the Trust.

     In May 2005, the FASB issued Statement of Financial Accounting Standards No. 154, “Accounting Changes and Error Corrections - A Replacement of APB Opinion No. 20 and FASB Statement No. 3.” SFAS No. 154 requires retrospective application, or the latest practical date, as the preferred method to report a change in accounting principle or correction of an error. SFAS No. 154 is effective for accounting changes and corrections of errors made in fiscal years beginning after December 15, 2005. This new standard has no impact on the financial statements of the Trust.

     In March 2005, the FASB issued FASB Interpretation No. 47, “Accounting for Conditional Asset Retirement Obligations,” (“FIN 47”). FIN 47 clarifies the term conditional asset retirement obligation and requires a liability to be recorded if the fair value of the obligation can be reasonably estimated. The types of asset retirement obligations that are covered by FIN 47 are those for which an entity has a legal obligation to perform an asset retirement activity; however the timing and/or method of settling the obligation are conditional on a future event that may or may not be within the control of the entity. FIN 47 is effective for fiscal years ending after December 15, 2005. This new standard has no impact on the financial statements of the Trust.

5. Federal Income Tax

     For Federal income tax purposes, the Trust constitutes a fixed investment trust which is taxed as a grantor trust. A grantor trust is not subject to tax at the trust level. The Unit holders are considered to own the Trust’s income and principal as though no trust were in existence. The income of the Trust is deemed to have been received or accrued by each Unit holder at the time such income is received or accrued by the Trust rather than when distributed by the Trust.

     The Royalties constitute “economic interests” in oil and gas properties for Federal income tax purposes. Unit holders must report their share of the revenues of the Trust as ordinary income from oil and gas royalties and are entitled to claim depletion with respect to such income.

     The Trust has on file technical advice memoranda confirming the tax treatment described above.

     The classification of the Trust’s income for purposes of the passive loss rules may be important to a Unit holder. Royalty income generally is treated as portfolio income and does not offset passive losses.

     Unit holders should consult their tax advisors for further information.

6. Significant Customers

     Information as to significant purchasers of oil and gas production attributable to the Trust’s economic interests is included in Item 2 of the Trust’s Annual Report on Form 10-K which is included in this report.

7. Proved Oil and Gas Reserves (Unaudited)

     Proved oil and gas reserve information is included in Item 2 of the Trust’s Annual Report on Form 10-K which is included in this report.

8. Quarterly Schedule of Distributable Income (Unaudited)

     The following is a summary of the unaudited quarterly schedule of distributable income for the two years ended December 31, 2005 (in thousands, except per Unit amounts):

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Unit Holders of Permian Basin Royalty Trust and Bank of America, N.A., Trustee:

We have audited the accompanying statements of assets, liabilities and trust corpus of Permian Basin Royalty Trust (the “Trust”) as of December 31, 2005 and 2004, and the related statements of distributable income and changes in trust corpus for each of the three years in the period ended December 31, 2005. These financial statements are the responsibility of the Trustee. Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

As described in Note 3 to the financial statements, these financial statements have been prepared on a modified cash basis of accounting which is a comprehensive basis of accounting other than accounting principles generally accepted in the United States of America.

In our opinion, such consolidated financial statements present fairly, in all material respects, the assets, liabilities and trust corpus of the Trust at December 31, 2005 and 2004, and the distributable income and changes in trust corpus for each of the three years in the period ended December 31, 2005, on the basis of accounting described in Note 3.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States), the effectiveness of the Trust’s internal control over financial reporting as of December 31, 2005, based on the criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated March 14, 2006 expressed an unqualified opinion on the Trustee’s assessment of the effectiveness of the Trust’s internal control over financial reporting and an unqualified opinion on the effectiveness of the Trust’s internal control over financial reporting.

/s/ Deloitte & Touche LLP

Dallas, Texas
March 14, 2006