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


                                    FORM 10-Q

                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended June 30, 2000


                         Commission File No. 33-26097-08

                        PARKER & PARSLEY 90-B CONV., L.P.
             (Exact name of Registrant as specified in its charter)


                   Delaware                                  75-2329284
   -----------------------------------------           ---------------------
        (State or other jurisdiction of                   (I.R.S. Employer
        incorporation or organization)                 Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ---------
          (Address of principal executive offices)                  (Zip code)

       Registrant's Telephone Number, including area code : (972) 444-9001


                                 Not applicable

              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the  preceding 12 months (or for such  shorter  period that the  Registrant  was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements for the past 90 days.

                                Yes / x / No / /





<PAGE>



                        PARKER & PARSLEY 90-B CONV., L.P.

                                TABLE OF CONTENTS


                                                                        Page

                          Part I. Financial Information

Item 1.    Financial Statements

           Balance Sheets as of June 30, 2000 and
              December 31, 1999.......................................    3

           Statements of Operations for the three and six
             months ended June 30, 2000 and 1999......................    4

           Statement of Partners' Capital for the six months
             ended June 30, 2000......................................    5

           Statements of Cash Flows for the six months ended
             June 30, 2000 and 1999...................................    6

           Notes to Financial Statements..............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations......................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K...........................   10

           27.1  Financial Data Schedule

           Signatures.................................................   11



                                        2


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                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.     Financial Statements
<TABLE>

                                 BALANCE SHEETS

                                                    June 30,      December 31,
                                                      2000            1999
                                                  ------------    -----------
                                                  (Unaudited)
                 ASSETS
<S>                                               <C>             <C>
Current assets:
   Cash                                           $   140,791     $   132,031
   Accounts receivable - oil and gas sales            169,409         143,411
                                                   ----------      ----------
         Total current assets                         310,200         275,442
                                                   ----------      ----------
Oil and gas properties - at cost, based on the
   successful efforts accounting method             9,623,172       9,612,816
Accumulated depletion                              (7,991,561)     (7,939,049)
                                                   ----------      ----------
         Net oil and gas properties                 1,631,611       1,673,767
                                                   ----------      ----------
                                                  $ 1,941,811     $ 1,949,209
                                                   ==========      ==========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
   Accounts payable - affiliate                   $    37,325     $    24,507

Partners' capital:
   Managing general partner                            19,043          19,246
   Limited partners (11,897 interests)              1,885,443       1,905,456
                                                   ----------      ----------
                                                    1,904,486       1,924,702
                                                   ----------      ----------
                                                  $ 1,941,811     $ 1,949,209
                                                   ==========      ==========
</TABLE>




   The financial information included as of June 30, 2000 has been prepared by
  the managing general partner without audit by independent public accountants.

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

                                        3


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                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



<TABLE>
                                    Three months ended       Six months ended
                                         June 30,                June 30,
                                  ---------------------   ---------------------
                                     2000        1999        2000        1999
                                  ---------   ---------   ---------   ---------
<S>                               <C>         <C>         <C>         <C>
Revenues:
  Oil and gas                     $ 356,486   $ 196,244   $ 687,189   $ 349,651
  Interest                            2,684         960       4,777       1,899
  Gain on disposition of assets         -           -         2,023         -
                                   --------    --------    --------    ------
                                    359,170     197,204     693,989     351,550
                                   --------    --------    --------    --------
Costs and expenses:
  Oil and gas production            143,700     115,052     277,308     236,655
  General and administrative         11,592       6,427      21,724      12,245
  Depletion                          25,752      29,386      52,512      90,929
                                   --------    --------    --------    --------
                                    181,044     150,865     351,544     339,829
                                   --------    --------    --------    --------
Net income                        $ 178,126   $  46,339   $ 342,445   $  11,721
                                   ========    ========    ========    ========
Allocation of net income:
  Managing general partner        $   1,781   $     463   $   3,424   $     117
                                   ========    ========    ========    ========
  Limited partners                $ 176,345   $  45,876   $ 339,021   $  11,604
                                   ========    ========    ========    ========
Net income per limited
  partnership interest            $   14.83   $    3.86   $   28.50   $     .98
                                   ========    ========    ========    ========
</TABLE>




         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

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

                                        4


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                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




<TABLE>

                                       Managing
                                       general        Limited
                                       partner        partners        Total
                                      ----------     ----------     ----------

<S>                                   <C>            <C>            <C>
Balance at January 1, 2000            $   19,246     $1,905,456     $1,924,702

    Distributions                         (3,627)      (359,034)      (362,661)

    Net income                             3,424        339,021        342,445
                                       ---------      ---------      ---------

Balance at June 30, 2000              $   19,043     $1,885,443     $1,904,486
                                       =========      =========      =========

</TABLE>





         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

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

                                        5


<PAGE>



                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)


<TABLE>
                                                            Six months ended
                                                                June 30,
                                                         ----------------------
                                                            2000        1999
                                                         ---------    ---------
<S>                                                      <C>          <C>
Cash flows from operating activities:
  Net income                                             $ 342,445    $  11,721
  Adjustments to reconcile net income to net
     cash provided by operating activities:
        Depletion                                           52,512       90,929
        Gain on disposition of assets                       (2,023)         -
  Changes in assets and liabilities:
        Accounts receivable                                (25,998)     (41,986)
        Accounts payable                                    12,818       12,495
                                                          --------     --------
            Net cash provided by operating activities      379,754       73,159
                                                          --------     --------
Cash flows from investing activities:
  Additions to oil and gas properties                      (10,356)      (5,828)
  Proceeds from asset dispositions                           2,023          -
                                                          --------     --------
            Net cash used in investing activities           (8,333)      (5,828)
                                                          --------     --------
Cash flows used in financing activities:
  Cash distributions to partners                          (362,661)     (46,886)
                                                          --------     --------
Net increase in cash equivalents                             8,760       20,445
Cash at beginning of period                                132,031       76,330
                                                          --------     --------
Cash at end of period                                    $ 140,791    $  96,775
                                                          ========     ========
</TABLE>



         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

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

                                        6


<PAGE>



                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                  June 30, 2000
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 90-B Conv., L.P. (the "Partnership") was organized as a general
partnership  in 1990 under the laws of the State of Texas and was converted to a
Delaware limited partnership on August 1, 1991.

The  Partnership  engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In  the  opinion  of  management,  the  unaudited  financial  statements  of the
Partnership  as of June 30, 2000 and for the three and six months ended June 30,
2000 and 1999 include all  adjustments  and accruals  consisting  only of normal
recurring accrual adjustments which are necessary for a fair presentation of the
results for the  interim  period.  These  interim  results  are not  necessarily
indicative of results for a full year. Certain  reclassifications  may have been
made to the June 30, 1999  financial  statements to conform to the June 30, 2000
financial statement presentations.

Certain  information  and footnote  disclosures  normally  included in financial
statements prepared in accordance with generally accepted accounting  principles
have been  condensed  or  omitted  in this Form 10-Q  pursuant  to the rules and
regulations of the Securities and Exchange Commission.  The financial statements
should  be read in  conjunction  with the  financial  statements  and the  notes
thereto  contained in the  Partnership's  Report on Form 10-K for the year ended
December 31, 1999, as filed with the Securities and Exchange Commission,  a copy
of which is available upon request by writing to Rich Dealy,  Vice President and
Chief Accounting Officer,  5205 North O'Connor  Boulevard,  1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations (1)

Results of Operations

Six months ended June 30, 2000 compared with six months ended June 30, 1999

Revenues:

The  Partnership's  oil and gas revenues  increased  97% to $687,189 for the six
months  ended June 30, 2000 as compared to $349,651 for the same period in 1999.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the six months ended June 30, 2000, 17,958 barrels

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of oil, 8,604 barrels of natural gas liquids ("NGLs") and 33,016 mcf of gas were
sold, or 32,065  barrel of oil  equivalents  ("BOEs").  For the six months ended
June 30, 1999, 18,107 barrels of oil, 8,670 barrel of NGLs and 36,322 mcf of gas
were sold, or 32,831 BOEs.

The average price  received per barrel of oil increased  $14.50,  or 110%,  from
$13.22 for the six months  ended June 30,  1999 to $27.72 for the same period in
2000. The average price received per barrel of NGLs  increased  $7.19,  or 106%,
from  $6.81  during the six  months  ended June 30,  1999 to $14.00 for the same
period in 2000.  The average  price  received per mcf of gas  increased 48% from
$1.41 for the six  months  ended June 30,  1999 to $2.08 for the same  period in
2000. The market price for oil and gas has been  extremely  volatile in the past
decade and management  expects a certain amount of volatility to continue in the
foreseeable  future.  The  Partnership may therefore sell its future oil and gas
production at average  prices lower or higher than that received  during the six
months ended June 30, 2000.

The volatility of commodity prices has had, and continues to have, a significant
impact on the Partnership's revenues and operating cash flow and could result in
additional  decreases to the  carrying  value of the  Partnership's  oil and gas
properties.

A gain on disposition  of assets of $2,023 was recognized  during the six months
ended June 30, 2000 from the sale of equipment on one fully depleted well.

Costs and Expenses:

Total costs and expenses increased to $351,544 for the six months ended June 30,
2000 as  compared  to  $339,829  for the same  period in 1999,  an  increase  of
$11,715,  or 3%. This  increase  was due to increases  in  production  costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production  costs  were  $277,308  for the six months  ended  June 30,  2000 and
$236,655 for the same period in 1999,  resulting in a $40,653 increase,  or 17%.
This  increase was the result of higher  production  taxes due to higher oil and
gas prices and  additional  well  maintenance  costs  incurred to stimulate well
production.

G&A's  components are independent  accounting and engineering  fees and managing
general  partner  personnel  and  operating  costs.   During  this  period,  G&A
increased, in aggregate, 77% from $12,245 for the six months ended June 30, 1999
to $21,724 for the same period in 2000  primarily due to a higher  allocation of
the managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Depletion was $52,512 for the six months ended June 30, 2000 compared to $90,929
for the same period in 1999, a decrease of $38,417,  or 42%.  This  decrease was
due to an increase in proved  reserves during the period ended June 30, 2000 due
to higher  commodity  prices, a decline in oil production of 149 barrels for the
six  months  ended  June 30,  2000  compared  to the same  period  in 1999 and a
reduction  in the  Partnership's  net  depletable  basis from  charges  taken in
accordance with Statement of Financial Accounting Standards No. 121, "Accounting
for the  Impairment  of Long-  Lived  Assets  and for  Long-Lived  Assets  to be
Disposed Of" ("SFAS 121") during the fourth quarter of 1999.

                                        8


<PAGE>



Three months ended June 30, 2000 compared with three months ended June 30, 1999

Revenues:

The Partnership's  oil and gas revenues  increased 82% to $356,486 for the three
months  ended June 30, 2000 as compared to $196,244 for the same period in 1999.
The increase in revenues resulted from higher average prices received, offset by
a decrease  in  production.  For the three  months  ended June 30,  2000,  8,968
barrels of oil, 4,625 barrels of NGLs and 17,395 mcf of gas were sold, or 16,492
BOEs.  For the three  months ended June 30, 1999,  8,675  barrels of oil,  4,896
barrels of NGLs and 18,753 mcf of gas were sold, or 16,697 BOEs.

The average  price  received per barrel of oil  increased  $12.94,  or 87%, from
$14.81 for the three months ended June 30, 1999 to $27.75 for the same period in
2000.  The average price received per barrel of NGLs  increased  $6.20,  or 78%,
from $7.90  during the three  months  ended June 30, 1999 to $14.10 for the same
period in 2000.  The average  price  received per mcf of gas  increased 57% from
$1.55  during the three  months ended June 30, 1999 to $2.44 for the same period
in 2000.

Costs and Expenses:

Total costs and  expenses  increased to $181,044 for the three months ended June
30, 2000 as compared  to  $150,865  for the same period in 1999,  an increase of
$30,179, or 20%. This increase was due to increases in production costs and G&A,
offset by a decline in depletion.

Production  costs were  $143,700  for the three  months  ended June 30, 2000 and
$115,052 for the same period in 1999,  resulting in a $28,648 increase,  or 25%.
The increase was the result of additional  well  maintenance  costs and workover
expenses  incurred to stimulate well production and higher  production taxes due
to higher oil and gas prices.

During this period, G&A increased,  in aggregate,  80% from $6,427 for the three
months  ended June 30, 1999 to $11,592  for the same period in 2000  principally
due to a higher allocation of the managing general partner's G&A being allocated
(limited to 3% of oil and gas  revenues)  as a result of  increased  oil and gas
revenues.

Depletion  was $25,752  for the three  months  ended June 30,  2000  compared to
$29,386 for the same period in 1999, a decrease of $3,634, or 12%. This decrease
was due to an increase in proved  reserves during the period ended June 30, 2000
as a result of higher commodity prices and a reduction in the  Partnership's net
depletable  basis  from  charges  taken in  accordance  with SFAS 121 during the
fourth  quarter of 1999,  offset by an increase in oil production of 293 barrels
for the three months ended June 30, 2000 compared to the same period in 1999.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash  provided by operating  activities  increased  $306,595  during the six
months  ended  June 30,  2000 from the same  period  ended June 30,  1999.  This

                                        9


<PAGE>


increase  resulted  from an increase of $356,404 in oil and gas sales  receipts,
offset by an increase in operating  costs paid of $42,652 and G&A expenses  paid
of $7,157.

Net Cash Used in Investing Activities

The Partnership's  principal investing  activities for the six months ended June
30, 2000 and 1999 included expenditures related to equipment upgrades on various
oil and gas properties.

Proceeds from asset  dispositions of $2,023 received during the six months ended
June 30, 2000 were  derived  from the sale of  equipment  on one fully  depleted
well.

Net Cash Used in Financing Activities

For the six months ended June 30, 2000, cash  distributions to the partners were
$362,661,  of which $3,627 was  distributed to the managing  general partner and
$359,034 to the limited partners.  For the same period ended June 30, 1999, cash
distributions to the partners were $46,886, of which $468 was distributed to the
managing general partner and $46,418 to the limited partners.

---------------

(1)   "Item 2. Management's  Discussion and Analysis of Financial  Condition and
      Results of Operations"  contains  forward looking  statements that involve
      risks and uncertainties.  Accordingly, no assurances can be given that the
      actual  events  and  results  will not be  materially  different  than the
      anticipated results described in the forward looking statements.

                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)   Exhibits

      27.1   Financial Data Schedule

(b)   Form 8-K - none


                                       10


<PAGE>


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)



                               S I G N A T U R E S



       Pursuant to the requirements of the Securities  Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.

                                           PARKER & PARSLEY 90-B CONV., L.P.

                                    By:    Pioneer Natural Resources USA, Inc.,
                                             Managing General Partner

Dated:  August 11, 2000             By:    /s/ Rich Dealy
                                           -------------------------------
                                           Rich Dealy, Vice President and
                                           Chief Accounting Officer

                                       11


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