<PAGE>   1





                                   FORM 10-Q
                       SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C.  20549

                   QUARTERLY REPORT UNDER SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                  FOR THE QUARTERLY PERIOD ENDED JUNE 30, 1998

                         COMMISSION FILE NUMBER 0-13465



                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
             (Exact name of registrant as specified in its charter)




<TABLE>
<S>                                                         <C>
             MARYLAND                                           52-1358879
   (State or other jurisdiction                              (I.R.S. Employer
of incorporation or organization)                           Identification No.)
</TABLE>




                       9200 KEYSTONE CROSSING, SUITE 500
                        INDIANAPOLIS, INDIANA 46240-7602
                    (Address of principal executive offices)
                                   (Zip Code)


                                 (317) 817-7500
              (Registrant's telephone number, including area code)

                                 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>   2





PART 1 - FINANCIAL INFORMATION

ITEM 1 - FINANCIAL STATEMENTS

                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
                        STATEMENTS OF FINANCIAL POSITION


<TABLE>
<CAPTION>
                                                                             June 30,
                                                                               1998              December 31,
                                                                           (Unaudited)               1997
                                                                        -----------------     ------------------

<S>                                                                    <C>                    <C>
                                     ASSETS
                                     ------

Cash and cash equivalents                                                 $     19,346          $     26,125
Investments in and advances to Local Limited Partnerships (Note 2)           1,811,607             1,780,933
                                                                          ------------          ------------

                                                                          $  1,830,953          $  1,807,058
                                                                          ============          ============

                   LIABILITIES AND PARTNERS' EQUITY (DEFICIT)
                   ------------------------------------------

Liabilities:
   Administrative and reporting fee payable to General Partner (Note 3)   $    873,160           $   829,964
   Due to General Partner (Note 3)                                               6,315                 6,315
   Accrued interest on partner loans (Note 3)                                      336                 -
   Accrued expenses                                                             59,820                40,210
                                                                          ------------           -----------

                                                                               939,631               876,489
                                                                          ------------           -----------

Partners  equity (deficit):
   General Partner -- The National Housing Partnership (NHP)                   (86,452)              (86,059)
   Original Limited Partner -- 1133 Fifteenth Street Associates                (91,352)              (90,959)
   Other Limited Partners -- 11,519 investment units                         1,069,126             1,107,587
                                                                          ------------           -----------

                                                                               891,322               930,569
                                                                          ------------           -----------

                                                                          $  1,830,953           $ 1,807,058
                                                                          ============           ===========
</TABLE>





                       See notes to financial statements.

                                      -1-
<PAGE>   3



                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
                            STATEMENTS OF OPERATIONS
                                  (UNAUDITED)



<TABLE>
<CAPTION>
                                                              Three Months Ended           Six Months Ended
                                                                 June 30,                       June 30,
                                                           -----------------------      --------------------
                                                               1998         1997          1998         1997
                                                           ------------ ----------      ---------- ---------

<S>                                                       <C>           <C>           <C>          <C>
REVENUES:
   Share of profits from Local Limited
    Partnerships (Note 2)                                 $    4,746    $     506      $  30,674   $     -
   Distributions and repayments received in excess
    of investment in Local Limited Partnerships                -           11,686          -          11,686
   Interest income                                                81          303            170         639
                                                          ----------    ---------      ---------   ---------

                                                               4,827       12,495         30,844      12,325
                                                          ----------    ---------      ---------   ---------

COSTS AND EXPENSES:
   Share of losses from Local Limited
    Partnerships (Note 2)                                      -            -              -          31,564
   Administrative and reporting fees to
    General Partner (Note 3)                                  21,598       21,598         43,196      43,196
   Interest on Partner loans                                     171          303            336         581
   Other operating expenses                                   12,108       11,320         26,559      24,282
                                                          ----------    ---------      ---------   ---------

                                                              33,877       33,221         70,091      99,623
                                                          ----------    ---------      ---------   ---------

NET LOSS                                                  $  (29,050)   $ (20,726)     $ (39,247)  $ (87,298)
                                                          ==========    =========      =========   =========

NET LOSS ASSIGNABLE TO
  LIMITED PARTNERS                                        $  (28,468)   $ (20,312)     $ (38,461)  $ (85,552)
                                                          ==========    =========      =========   =========

NET LOSS PER LIMITED
  PARTNERSHIP INTEREST                                    $       (2)   $      (2)     $      (3)  $      (7)
                                                          ==========    =========      ==========  =========
</TABLE>





                       See notes to financial statements.

                                      -2-
<PAGE>   4



                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
                    STATEMENT OF PARTNER'S EQUITY (DEFICIT)
                                  (UNAUDITED)


<TABLE>
<CAPTION>
                                         The National         1133
                                           Housing         Fifteenth          Other
                                         Partnership         Street          Limited
                                            (NHP)          Associates        Partners          Total
                                         -----------       ----------        --------          -----

<S>                                       <C>              <C>             <C>               <C>
Equity (deficit) at January 1, 1998       $(86,059)        $(90,959)       $1,107,587        $ 930,569

Net loss -- six months ended
  June 30, 1998                               (393)            (393)         (38,461)         (39,247)
                                          --------         --------        ---------         --------

Equity (deficit) at June 30, 1998         $(86,452)        $(91,352)       $1,069,126        $ 891,322
                                          ========         ========        ==========        =========

Percentage interest at
 June 30, 1998                                   1%               1%              98%             100%
                                          ========         ========        =========         ========
                                                (A)              (B)              (C)
</TABLE>

(A)      General Partner
(B)      Original Limited Partner
(C)      Consists of 11,519 investment units of 0.0085% held by 1,111 investors





                       See notes to financial statements.

                                      -3-
<PAGE>   5



                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
                            STATEMENTS OF CASH FLOWS
                                  (UNAUDITED)


<TABLE>
<CAPTION>
                                                                          Six Months Ended June 30,
                                                                  --------------------------------------
                                                                      1998                      1997
                                                                  ------------              ------------

<S>                                                              <C>                       <C>
CASH FLOWS FROM OPERATING ACTIVITIES:
   Distributions received in excess of investment in
    Local Limited Partnerships                                   $      -                  $   11,686
   Interest received                                                     170                      639
   Operating expenses paid                                            (6,949)                 (43,702)
                                                                 -----------               ----------

Net cash used in operating activities                                 (6,779)                 (31,377)

CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD                        26,125                   62,193
                                                                 -----------               ----------

CASH AND CASH EQUIVALENTS, END OF PERIOD                         $    19,346               $   30,816
                                                                 ===========               ==========

RECONCILIATION OF NET LOSS TO NET
  CASH USED IN OPERATING ACTIVITIES:
     Net loss                                                    $   (39,247)              $  (87,298)
                                                                 -----------               ----------
     Adjustments to reconcile net loss to net cash
       used in operating activities:
          Share of (profits) losses from Local Limited
            Partnerships                                             (30,674)                  31,564
          Increase in administrative and reporting fees payable       43,196                   43,196
          Increase in accrued interest on Partner loans                  336                      581
          Increase (decrease) in other accrued expenses               19,610                  (19,420)
                                                                 -----------               ----------

            Total adjustments                                         32,468                   55,921
                                                                 -----------               ----------

     Net cash used in operating activities                       $    (6,779)              $  (31,377)
                                                                 ===========               ==========
</TABLE>





                       See notes to financial statements.

                                      -4-
<PAGE>   6
                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
                         NOTES TO FINANCIAL STATEMENTS



(1)      ACCOUNTING POLICIES

         ORGANIZATION

         National Housing Partnership Realty Fund I (the "Partnership") is a
         limited partnership organized under the laws of the State of Maryland
         under the Maryland Revised Uniform Limited Partnership Act on October
         21, 1983. The Partnership was formed for the purpose of raising
         capital by offering and selling limited partnership interests and then
         investing in limited partnerships ("Local Limited Partnerships"), each
         of which owns and operates an existing rental housing project which is
         financed and/or operated with one or more forms of rental assistance
         or financial assistance from the U.S.  Department of Housing and Urban
         Development ("HUD").

         The General Partner raised capital for the Partnership by offering and
         selling to additional limited partners 11,519 investment units at a
         price of $1,000 per unit. The Partnership acquired limited partnership
         interests ranging from 98% to 99% in ten Local Limited Partnerships,
         each of which was organized to acquire and operate an existing rental
         housing project.

         On June 3, 1997, Apartment Investment and Management Company, a
         Maryland corporation ("AIMCO" and, together with its subsidiaries and
         other controlled entities, the "AIMCO Group"), acquired all of the
         issued and outstanding capital stock of NHP Partners, Inc., a Delaware
         corporation ("NHP Partners"), and the AIMCO Group acquired all of the
         outstanding interests in NHP Partners Two Limited Partnership, a
         Delaware limited partnership ("NHP Partners Two"). The Acquisition was
         made pursuant to a Real Estate Acquisition Agreement, dated as of May
         22, 1997 (the "Agreement"), by and among AIMCO, AIMCO Properties,
         L.P., a Delaware limited partnership (the "Operating Partnership"),
         Demeter Holdings Corporation, a Massachusetts corporation ("Demeter"),
         Phemus Corporation, a Massachusetts corporation ("Phemus"), Capricorn
         Investors, L.P., a Delaware limited partnership ("Capricorn"), J.
         Roderick Heller, III and NHP Partners Two LLC, a Delaware limited
         liability company ("NHP Partners Two LLC"). NHP Partners owns all of
         the outstanding capital stock of the National Corporation for Housing
         Partnerships, a District of Columbia corporation ("NCHP"), which is
         the general partner of The National Housing Partnership, a District of
         Columbia limited partnership ("NHP"). Together, NCHP and NHP Partners
         Two own all of the outstanding partnership interests in the NHP. NHP
         is the general partner of National Housing Partnership Realty Fund I
         (a Maryland Limited Partnership) (the "Registrant"). As a result of
         these transactions, the AIMCO Group has acquired control of the
         general partner of the Registrant and, therefore, may be deemed to
         have acquired control of the Registrant.

         The Original Limited Partner of the Partnership is 1133 Fifteenth
         Street Associates, whose limited partners were key employees of NCHP
         at the time the Partnership was formed and whose general partner is
         NHP.

         BASIS OF PRESENTATION

         The accompanying unaudited interim financial statements reflect all
         adjustments which are, in the opinion of management, necessary to a
         fair statement of the financial condition and results of operations
         for the interim periods presented. All such adjustments are of a
         normal and recurring nature.

         While the General Partner believes that the disclosures presented are
         adequate to make the information not misleading, it is suggested that
         these financial statements be read in conjunction with the financial
         statements and notes included in NHP Realty Fund I's Annual Report
         filed in Form 10-K for the year ended December 31, 1997.





                                      -5-
<PAGE>   7
                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
                         NOTES TO FINANCIAL STATEMENTS



(2)      INVESTMENTS IN AND ADVANCES TO LOCAL LIMITED PARTNERSHIPS

         The Partnership owns a 98% limited partnership interest in Gates Mills
         I Limited Partnership and 99% limited partnership interests in nine
         other Local Limited Partnerships. Because the Partnership, as a
         limited partner, does not exercise control over the activities of the
         Local Limited Partnerships in accordance with the partnership
         agreements, the investments in Local Limited Partnerships are
         accounted for using the equity method. Thus, the investments (and the
         advances made to the Local Limited Partnerships as discussed below)
         are carried at cost plus the Partnership's share of the Local Limited
         Partnerships' profits less the Partnership's share of the Local
         Limited Partnerships' losses and distributions. However, because the
         Partnership is not legally liable for the obligations of the Local
         Limited Partnerships, and is not otherwise committed to provide
         additional support to them, it does not recognize losses once its
         investments, reduced for its share of losses and cash distributions,
         reach zero in each of the individual Local Limited Partnerships. As of
         June 30, 1998 and December 31, 1997, investments in eight of the ten
         Local Limited Partnerships had been reduced to zero. As a result, the
         Partnership did not recognize $640,385 and $708,110 of losses from
         Local Limited Partnerships during the six months ended June 30, 1998
         and 1997, respectively. As of June 30, 1998 and December 31, 1997, the
         Partnership has not recognized a total of $16,450,898 and $15,810,513,
         respectively, of its allocated share of cumulative losses from the
         Local Limited Partnerships in which its investment is zero.

         Advances made by the Partnership to the individual Local Limited
         Partnerships are considered part of the Partnership's investment in
         Local Limited Partnerships. When advances are made to a Local Limited
         Partnership for which the Partnership carries its investment at zero,
         they are charged to operations as a loss on investment in the Local
         Limited Partnership using previously unrecognized cumulative losses.
         As discussed above, due to the cumulative losses incurred by eight of
         the Local Limited Partnerships, the aggregate balance of investments
         in and advances to Local Limited Partnerships, for these eight Local
         Limited Partnerships, has been reduced to zero at June 30, 1998 and
         December 31, 1997. To the extent these advances are repaid by the
         Local Limited Partnerships in the future, the repayments will be
         credited as distributions in excess of investment in Local Limited
         Partnerships. These advances are carried as a payable to the
         Partnership by the Local Limited Partnerships.

         During the six months ended June 30, 1998 and 1997, no working capital
         advances or repayments were made between the Partnership and the Local
         Limited Partnerships. The combined amount carried as due to the
         Partnership by the Local Limited Partnerships was $376,951 as of June
         30, 1998.

         The following are combined statements of operations for the three and
         six months ended June 30, 1998 and 1997, respectively, of the Local
         Limited Partnerships in which the Partnership has invested. The
         statements are compiled from financial statements of the Local Limited
         Partnerships, prepared on the accrual basis of accounting, as supplied
         by the management agents of the projects, and are unaudited.





                                      -6-
<PAGE>   8
                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
                         NOTES TO FINANCIAL STATEMENTS



                       COMBINED STATEMENTS OF OPERATIONS


<TABLE>
<CAPTION>
                                              Three Months Ended              Six Months Ended
                                                  June 30,                        June 30,
                                        ------------------------------    ----------------------------
                                            1998             1997             1998             1997
                                        -------------- ---------------    -------------- -------------

<S>                                     <C>              <C>              <C>              <C>
Rental income                           $ 1,811,189      $ 1,822,124      $3,649,013       $3,656,556
Other income                                 53,200           49,752         107,334           94,056
                                        -----------      -----------      ----------       ----------

   Total income                           1,864,389        1,871,876       3,756,347        3,750,612
                                        -----------      -----------      ----------       ----------

Operating expenses                        1,306,789        1,303,585       2,561,332        2,649,537
Interest, taxes and insurance               592,789          608,262       1,216,989        1,253,924
Depreciation                                297,829          296,250         595,737          595,909
                                        -----------      -----------      ----------       ----------

   Total expenses                         2,197,407        2,208,097       4,374,058        4,499,370
                                        -----------      -----------      ----------       ----------

Net loss                                $ (333,018)      $ (336,221)      $ (617,711)      $ (748,758)
                                        ==========       ==========       ==========       ==========

National Housing Partnership
  Realty Fund I share of losses         $ (328,836)      $ (332,148)      $ (609,711)      $ (739,674)
                                        ==========       ==========       ==========       ==========
</TABLE>


(3)    TRANSACTIONS WITH THE GENERAL PARTNER

         During the six month periods ended June 30, 1998 and 1997, the
         Partnership accrued administrative and reporting fees payable to the
         General Partner in the amount of $43,196 for services provided to the
         Partnership. The Partnership did not make any payments to the General
         Partner for these fees during each of the respective periods. The
         amount due the General Partner by the Partnership for administrative
         and reporting fees was $873,160 and $829,964 at June 30, 1998 and
         December 31, 1997, respectively.

         During the six months ended June 30, 1998 and 1997, no working capital
         advances or repayments were made between the General Partner and the
         Partnership. The amount owed to the General Partner at June 30, 1998
         and December 31, 1997, was $6,315.  Interest is charged on borrowings
         at the Chase Manhattan Bank rate of prime plus 2%. Chase Manhattan
         Bank prime was 8.5% at June 30, 1998. Accrued interest on this loan
         amounted to $336 and zero at June 30, 1998 and December 31, 1997,
         respectively.

         The advances and accrued administrative and reporting fees payable to
         the General Partner will be paid as cash flow permits or from proceeds
         generated from the sale or refinancing of one or more of the
         underlying properties of the Local Limited Partnerships.





                                      -7-
<PAGE>   9




ITEM 2 -         MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
                 AND RESULTS OF OPERATIONS

                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)


The Private Securities Litigation Reform Act of 1995 provides a "safe harbor"
for forward-looking statements in certain circumstances. Certain information
included in this Report and other Partnership filings (collectively "SEC
Filings") under the Securities Act of 1933, as amended, and the Securities
Exchange Act of 1934, as amended (as well as information communicated orally or
in writing between the dates of such SEC Filings) contains or may contain
information that is forward-looking, including statements regarding the effect
of government regulations. Actual results may differ materially from those
described in the forward-looking statements and will be affected by a variety
of factors including national and local economic conditions, the general level
of interest rates, terms of governmental regulations that affect the
Partnership and interpretations of those regulations, the competitive
environment in which the properties owned by the Local Limited Partnerships
operate, the availability of working capital and dispositions of properties
owned by the Partnership.

LIQUIDITY AND CAPITAL RESOURCES

The properties in which the Partnership has invested, through its investments
in the Local Limited Partnerships, receive one or more forms of assistance from
Federal, state or local governments or agencies. As a result, the Local Limited
Partnerships' ability to transfer funds either to the Partnership or among
themselves in the form of cash distributions, loans or advances is generally
restricted by these government-assistance programs. These restrictions,
however, are not expected to impact the Partnership's ability to meet its cash
obligations.

For the past several years, various proposals have been advanced by the United
States Department of Housing and Urban Development ("HUD"), Congress and others
proposing the restructuring of HUD's rental assistance programs under Section 8
of the United States Housing Act of 1937 ("Section 8"), under which 1,213
units, 77 percent of the total units owned by the properties in which the
Partnership has invested, receive rental subsidies. On October 27, 1997, the
President signed into law the Multifamily Assisted Housing Reform and
Affordability Act of 1997 (the "1997 Housing Act"). Under the 1997 Housing Act,
certain properties assisted under Section 8, with rents above market levels and
financed with HUD-insured mortgage loans, will be restructured by adjusting
subsidized rents to market levels, thereby potentially reducing rent subsidies,
and lowering required debt service costs as needed to ensure financial
viability at the reduced rents and rent subsidies. The 1997 Housing Act retains
project-based subsidies for most properties (properties in rental markets with
limited supply, properties serving the elderly, and certain other properties).
The 1997 Housing Act phases out project-based subsidies on selected properties,
servicing families not located in rental markets with limited supply,
converting such subsidies to a tenant-based subsidy. Under a tenant-based
system, rent vouchers would be issued to qualified tenants who then could elect
to reside at properties of their choice, provided such tenants have the
financial ability to pay the difference between the selected properties
monthly rent and the value of the vouchers, which would be established based on
HUD's regulated fair market rent for the relevant geographical areas. The 1997
Housing Act provides that properties will begin the restructuring process in
federal fiscal year 1999 (beginning October 1, 1998), and that HUD will issue
final regulations implementing 1997 Housing Act on or before October 27, 1998.
With respect to Housing Assistance Payments Contracts ("HAP Contracts")
expiring before October 1, 1998, Congress has elected to renew them for
one-year terms, generally at existing rents, so long as the properties remain
in compliance with the HAP Contracts. While the Partnership does not expect the
provisions of the 1997 Housing Act to result in a significant number of tenants
relocating from properties owned by the Local Limited Partnerships, there can
be no assurance that the provisions will not significantly affect the
operations of the properties of the Local Limited Partnerships.  Furthermore,
there can be no assurance that other changes in Federal housing subsidy policy
will not occur. Any such changes could have an adverse effect on the operation
of the Partnership.





                                      -8-
<PAGE>   10
                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
          MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
                           AND RESULTS OF OPERATIONS





Net cash used in operations for the six months ended June 30, 1998 was $6,779
as compared to cash used in operations of $31,377 for the six months ended June
30, 1997. The decrease in cash used in operations resulted from a decrease in
operating expenses paid, partially offset by a decrease in distributions
received in excess of investment in Local Limited Partnerships.

During the six months ended June 30, 1998 and 1997, no working capital advances
or repayments were made between the Partnership and the Local Limited
Partnerships. The combined amount carried as due to the Partnership by the
Local Limited Partnerships was $376,951 as of June 30, 1998.

Distributions received from Local Limited Partnerships represent the
Partnership's proportionate share of the excess cash available for distribution
from the Local Limited Partnerships. As a result of the use of the equity
method of accounting for the Partnership's investments, as of June 30, 1998,
investments in eight Local Limited Partnerships had been reduced to zero. For
these investments, cash distributions received are recorded in income as
distributions received in excess of investment in Local Limited Partnerships.
For those investments not reduced to zero, distributions received are recorded
as distributions from Local Limited Partnerships. There were no cash
distributions during the six months ended June 30, 1998. Cash distributions of
$11,686 were received during the six months ended June 30, 1997. The receipt of
distributions in future quarters and years is dependent upon the operations of
the underlying properties of the Local Limited Partnerships to generate
sufficient cash for distribution in accordance with applicable HUD regulations.

Cash and cash equivalents amounted to $19,346 at June 30, 1998. The ability of
the Partnership to meet its on-going cash requirements, in excess of cash on
hand at June 30, 1998, is dependent upon the future receipt of distributions
from the Local Limited Partnerships or proceeds from sales or refinancing of
one or more of the underlying properties of the Local Limited Partnerships.
Cash on hand at June 30, 1998, plus any distributions from the underlying
operations of the combined Local Limited Partnerships is expected to adequately
fund the operations of the Partnership in the current year. However, there can
be no assurance that future distributions will be adequate to fund the
operations beyond the current year.

The Partnership currently owes the General Partner $873,160 for administrative
and reporting services performed. The payment of the unpaid administrative and
reporting fees will most likely result from the sale or refinancing of the
underlying properties of the Local Limited Partnerships, rather than through
recurring operations.

Eight of the Local Limited Partnerships in which the Partnership has invested
have deferred acquisition notes due the original owner of each Property. With
the exception of Fairmeadows and Southridge, these notes have matured or will
reach final maturity prior to December, 1999. These notes are secured by both
the Partnership's and NHP's interests in the Local Limited Partnerships. In the
event of a default on the notes, the note holders would be able to assume NHP's
and the Partnership's interests in the Local Limited Partnerships.

Griffith Limited Partnership has defaulted on its deferred acquisition note and
related accrued interest which became due on October 31, 1997, which raises
substantial doubt about the Local Limited Partnership's ability to continue as a
going concern with its present ownership structure. The Local Limited
Partnership's continued existence as a going concern with its present ownership
structure is dependent on the ability to repay, refinance, restructure, or
renegotiate this note. The General Partner is currently negotiating to extend
the note and maintain ownership of the property. Should no agreement be reached
and the note matures absent a sale or refinancing which produces sufficient
funds to repay the note in full, a default would occur on the note. Such default
could lead to a foreclosure by the note holder of the security underlying the
note such that the Partnership may lose its interest in the Griffith Limited
Partnership. Should the Partnership lose its interest in Griffith Limited
Partnership, partners in the Partnership may incur adverse tax consequences. The
impact of the tax consequences is dependent upon each partner's individual tax
situation.





                                      -9-
<PAGE>   11
                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
          MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
                           AND RESULTS OF OPERATIONS





Southward Limited Partnership and Northgate Village Limited Partnership have
deferred acquisition notes and related accrued interest due on October 4, 1998
and July 26, 1999, respectively, which raises substantial doubt about the Local
Limited Partnerships' ability to continue as going concerns with their present
ownership structure. The Local Limited Partnerships' continued existence as
going concerns with their present ownership structure is dependent on the
ability to repay, refinance, restructure, or renegotiate these notes. Should no
agreement be reached and the notes mature absent any sales or refinancing which
produce sufficient funds to repay the notes in full, a default would occur on
the notes. Such defaults could lead to a foreclosure by the note holders of the
security underlying the notes such that the Partnership may lose its interests
in the Local Limited Partnerships. Should the Partnership lose its interests in
the Local Limited Partnerships, partners in the Partnership may incur adverse
tax consequences. The impact of the tax consequences is dependent upon each
partner s individual tax situation.

San Jose Limited Partnership, Gates Mills I Limited Partnership and Hurbell IV
Limited Partnership have deferred acquisition notes and related accrued
interest due on August 29, 1999, October 1, 1999 and November 9, 1999,
respectively. Should the notes mature absent any sales or refinancing which
produce sufficient funds to repay the notes in full, a default would occur on
the notes. Such defaults could lead to a foreclosure by the note holders of the
security underlying the notes such that the Partnership may lose its interests
in the Local Limited Partnerships. Should the Partnership lose its interests in
the Local Limited Partnerships, partners in the Partnership may incur adverse
tax consequences. The impact of the tax consequences is dependent upon each
partner s individual tax situation.

RESULTS OF OPERATIONS

The Partnership has invested as a limited partner in Local Limited Partnerships
which operate ten rental housing properties. In prior years, results of
operations of NHP Realty Fund I were significantly impacted by the
Partnership's share of the losses of the Local Limited Partnerships. These
losses included depreciation and accrued deferred acquisition note interest
expense which are noncash in nature. Eight of the ten investments in Local
Limited Partnerships have been reduced to zero. As a result, the Partnership's
operations are no longer being affected by its share of the operations from
these eight partnerships. The Partnership has recorded its share of operations
in the remaining two Local Limited Partnerships which amounted to profits of
$30,674 for the six months ended June 30, 1998, and losses of $31,564 for the
six months ended June 30, 1997.

The Partnership realized a net loss of $39,247 for the six months ended June
30, 1998, compared to a net loss of $87,298 for the six months ended June 30,
1997. Net loss per unit of limited partnership interest decreased from $7 to $3
for the 11,519 units outstanding for both periods. The decrease in net loss was
primarily due to the Partnerships' share of profits from Local Limited
Partnerships of $30,674 recognized in 1998, compared to the Partnerships' share
of losses from Local Limited Partnerships of $31,564 recognized in 1997. The
Partnership did not recognize $640,385 of its allocated share of losses from
eight Local Limited Partnerships for the six months ended June 30, 1998, as the
Partnership's net carrying basis in these Local Limited Partnerships had been
reduced to zero. The Partnership's share of operating losses from the Local
Limited Partnerships, if not limited to its investment account balance, would
have decreased $129,963 between periods, primarily due to a decrease in
operating expenses.





                                      -10-
<PAGE>   12
                   NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                        (A MARYLAND LIMITED PARTNERSHIP)
          MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
                           AND RESULTS OF OPERATIONS





PART II - OTHER INFORMATION

ITEM 6  - EXHIBITS AND REPORTS ON FORM 8-K

          (a)    Exhibits

                 Exhibit No.
                 -----------
   
                 27       Financial Data Schedule.





                                      -11-

<PAGE>   13

                                   SIGNATURES



         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.



<TABLE>
<S>                               <C>
                                  NATIONAL HOUSING PARTNERSHIP REALTY FUND I
                                  ------------------------------------------
                                  (Registrant)


                                  By:     The National Housing Partnership,
                                          its sole General Partner


                                  By:     National Corporation for Housing
                                          Partnerships, its sole General Partner



August 14, 1998                   By:                        /s/  
---------------                           ----------------------------------------------------
                                          Troy D. Butts
                                          As Senior Vice President and Chief Financial Officer
</TABLE>





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