<PAGE>   1
                                      1999
================================================================================
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

                                 FORM 10-QSB/A


( Mark One)
[X]  Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange
     Act of 1934 For the quarterly period ended March 31, 1999.
                                       or
[ ]  Transition Report Pursuant to Section 13 or 15(d) of the Securities
     Exchange Act of 1934 For the transition period from ________ to ___________


Commission file number:  0-12742


                                SPIRE CORPORATION
--------------------------------------------------------------------------------
        (Exact Name of Small Business Issuer as Specified in Its Charter)


        MASSACHUSETTS                                    04-2457335
--------------------------------------------------------------------------------
(State or Other Jurisdiction of             (I.R.S. Employer Identification No.)
 Incorporation or Organization


 ONE PATRIOTS PARK, BEDFORD, MASSACHUSETTS                            01730-2396
--------------------------------------------------------------------------------
(Address of Principal Executive Offices)                             (Zip Code)


                                  781-275-6000
--------------------------------------------------------------------------------
                (Issuer's Telephone Number, Including Area Code)


     Check whether the issuer: (1) filed all reports required to be filed by
Section 13 or 15(d) of the Exchange Act during the past 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 [ ]


     State the number of shares outstanding of each of the issuer's classes of
common equity, as of the latest practicable date. There were 3,243,766
outstanding shares of the issuer's only class of common equity, Common Stock,
$.01 par value, on April 30, 1999.


     Transitional Small Business Disclosure Format (Check One):
Yes [ ] No [X]


<PAGE>   2


                                SPIRE CORPORATION
                                      INDEX


<TABLE>
<CAPTION>
                                                                                                            PAGE NUMBER
                                                                                                            -----------
PART I - FINANCIAL INFORMATION
------------------------------

<S>                                                                                                              <C>
    Condensed Consolidated Balance Sheets at                                                                     3
    March 31, 1999 (unaudited) and December 31, 1998

    Condensed Consolidated Statements of Operations                                                              4
    For the Three Months Ended March 31, 1999 and 1998 (unaudited)

    Condensed Consolidated Statements of Cash Flows                                                              5
    For the Three Months Ended March 31, 1999 and 1998 (unaudited)

    Notes to Condensed Consolidated Financial Statements                                                         6

    Management's Discussion and Analysis of Financial Condition and Results of
    Operations                                                                                                 7 - 10


PART II - OTHER INFORMATION
---------------------------

    Item 1.  Legal Proceedings                                                                                   10

    Item 6.  Exhibits and Reports on Form 8-K                                                                    10
</TABLE>


                                       2
<PAGE>   3


                        SPIRE CORPORATION AND SUBSIDIARY
                      CONDENSED CONSOLIDATED BALANCE SHEETS

<TABLE>
<CAPTION>
                                                                                                   MARCH 31,           DECEMBER 31,
                                                                                                     1999                  1998
                                                                                                 --------------        ------------
<S>                                                                                                    <C>                <C>
                                           ASSETS
CURRENT ASSETS
--------------
    Cash and cash equivalents                                                                        $   96,558         $   121,866
    Accounts receivable, trade:
        Amounts billed                                                                                2,275,734           2,799,037
        Retainage                                                                                        62,173              62,173
        Unbilled costs                                                                                  362,451             355,716
                                                                                                 --------------        ------------
                                                                                                      2,700,358           3,216,926
        Less allowance for doubtful accounts                                                            102,000             102,000
                                                                                                 --------------        ------------
            Net accounts receivable                                                                   2,598,358           3,114,926
                                                                                                 --------------        ------------

    Inventories (Note 2)                                                                              1,718,447           2,254,043
    Prepaid expenses and other current assets                                                           341,063             363,649
                                                                                                 --------------        ------------
            Total current assets                                                                      4,754,426           5,854,484
                                                                                                 --------------        ------------

Property and equipment                                                                               25,968,978          25,675,700
    Less accumulated depreciation and amortization                                                   21,223,977          20,986,170
                                                                                                 --------------        ------------
            Net property and equipment                                                                4,745,001           4,689,530
                                                                                                 --------------        ------------

Patents (less accumulated amortization, $624,758 in 1999 and $611,650 in 1998)                          210,136             214,758
Other assets                                                                                             29,087              15,071
                                                                                                 --------------        ------------
                                                                                                        239,223             229,829
                                                                                                 --------------        ------------
                                                                                                     $9,738,650         $10,773,843
                                                                                                 ==============        ============

                            LIABILITIES AND STOCKHOLDERS' EQUITY
CURRENT LIABILITIES
-------------------
    Accounts payable                                                                                 $1,470,984          $1,555,019
    Accrued liabilities                                                                                 876,430             836,846
    Notes payable                                                                                       550,000             850,000
    Advances on contracts in progress                                                                   570,469           1,112,058
                                                                                                 --------------        ------------
        Total current liabilities                                                                     3,467,883           4,353,923
                                                                                                 --------------        ------------

STOCKHOLDERS' EQUITY
--------------------
    Common stock, $.01 par value; shares authorized 20,000,000;
        issued 3,795,926 shares in 1999 and 1998                                                         37,959              37,959
    Additional paid-in capital                                                                        9,780,494           9,780,494
    Accumulated deficit                                                                              (2,327,998)         (2,178,845)
                                                                                                 --------------        ------------
                                                                                                      7,490,455           7,639,608
    Treasury stock at cost, 552,160 shares                                                           (1,219,688)         (1,219,688)
                                                                                                 --------------        ------------
        Total stockholders' equity                                                                    6,270,767           6,419,920
                                                                                                 --------------        ------------
                                                                                                     $9,738,650         $10,773,843
                                                                                                 ==============        ============
</TABLE>

     See accompanying notes to condensed consolidated financial statements.


                                       3
<PAGE>   4


                        SPIRE CORPORATION AND SUBSIDIARY
                 CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS


<TABLE>
<CAPTION>
                                                                                                     THREE MONTHS ENDED MARCH 31,
                                                                                                 -----------------------------------
                                                                                                      1999                  1998
                                                                                                 --------------         ------------

<S>                                                                                                  <C>                  <C>
NET SALES AND REVENUES
----------------------
    Contract research, service and license revenues                                                  $2,655,097           $3,115,886
    Sales of manufacturing equipment                                                                  1,162,619            1,326,640
                                                                                                 --------------         ------------
        Total sales and revenues                                                                      3,817,716            4,442,526
                                                                                                 --------------         ------------

COSTS AND EXPENSES
------------------
    Cost of contract research, services and licenses                                                  1,816,022            2,207,178
    Cost of manufacturing equipment                                                                   1,006,425              803,761
    Selling, general and administrative expenses                                                      1,117,623            1,417,765
                                                                                                 --------------         ------------
        Total costs and expenses                                                                      3,940,070            4,428,704
                                                                                                 --------------         ------------

EARNINGS (LOSS) FROM OPERATIONS                                                                        (122,354)              13,822
-------------------------------

Interest income (expense), net                                                                          (26,799)              12,337
                                                                                                 --------------         ------------

Earnings (loss) before income taxes                                                                    (149,153)              26,159

Income tax expense                                                                                           --                9,000
                                                                                                 --------------         ------------

NET EARNINGS (LOSS)                                                                                  $ (149,153)          $   17,159
-------------------                                                                              ==============         ============

EARNINGS (LOSS) PER SHARE OF COMMON STOCK - BASIC                                                    $    (0.05)          $     0.01
-------------------------------------------------                                                ==============         ============

EARNINGS (LOSS) PER SHARE OF COMMON STOCK - DILUTED                                                  $    (0.05)          $     0.01
---------------------------------------------------                                              ==============         ============

Weighted average number of common shares outstanding - basic                                          3,243,766            3,216,869
                                                                                                 ==============         ============

Weighted average number of common and  common equivalent shares
    outstanding - diluted                                                                             3,243,766            3,350,910
                                                                                                 ==============         ============
</TABLE>

     See accompanying notes to condensed consolidated financial statements.


                                       4
<PAGE>   5


                        SPIRE CORPORATION AND SUBSIDIARY
                 CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS


<TABLE>
<CAPTION>
                                                                                                      THREE MONTHS ENDED MARCH 31,
                                                                                                 -----------------------------------
                                                                                                     1999                   1998
                                                                                                 --------------         ------------

<S>                                                                                                 <C>                   <C>
Cash flows from operating activities:
    Net earnings (loss)                                                                             $ (149,153)           $  17,159
    Adjustments to reconcile net earnings (loss) to net cash used in
        operating activities:
            Depreciation and amortization                                                              250,914              239,144
            Changes in assets and liabilities:
                Accounts receivable                                                                    516,568             (371,064)
                Inventories                                                                            535,596             (687,250)
                Prepaid expenses and other current assets                                               22,586             (143,162)
                Accounts payable and accrued liabilities                                               (44,451)             (31,192)
                Advances on contracts in progress                                                     (541,589)             226,624
                                                                                                 --------------         ------------
                     Net cash provided by (used in) by operating activities                            590,471             (749,741)
                                                                                                 --------------         ------------

Cash flows from investing activities:
    Additions to property and equipment                                                               (293,278)            (366,631)
    Increase in patent costs                                                                            (8,485)              (4,411)
    Other assets                                                                                       (14,016)               1,908
                                                                                                 --------------         ------------
                 Net cash used in investing activities                                                (315,779)            (369,134)
                                                                                                 --------------         ------------

Cash flows from financing activities:
    Net receipts (payments) on short-term debt                                                        (300,000)                  --
    Exercise of stock options                                                                               --              114,792
                                                                                                 --------------         ------------
                      Net cash provided by (used in) financing activities                             (300,000)             114,792
                                                                                                 --------------         ------------

Net decrease in cash and cash equivalents                                                              (25,308)          (1,004,083)

Cash and cash equivalents, beginning of period                                                         121,866            1,695,727
                                                                                                 --------------         ------------
Cash and cash equivalents, end of period                                                              $ 96,558            $ 691,644
                                                                                                 ==============         ============

Supplemental disclosures of cash flow information: Cash paid during the year
        for:
            Interest expense                                                                          $ 22,573             $    723
                                                                                                 ==============         ============
            Income taxes                                                                              $  3,000            $  44,400
                                                                                                 ==============         ============
</TABLE>

     See accompanying notes to condensed consolidated financial statements.


                                       5
<PAGE>   6


                        SPIRE CORPORATION AND SUBSIDIARY
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

                                 MARCH 31, 1999

(1)  Interim Financial Statements
     ----------------------------

          In the opinion of management, the accompanying unaudited condensed
     consolidated financial statements contain all adjustments necessary to
     fairly present the Company's financial position as of March 31, 1999, the
     results of operations for the three months ended March 31, 1999 and 1998,
     and changes in cash flows for the three months ended March 31, 1999 and
     1998. The results of operations for the three months ended March 31, 1999
     are not necessarily indicative of the results to be expected for the fiscal
     year ending December 31, 1999.

          The accounting policies followed by the Company are set forth in Note
     2 to the Company's consolidated financial statements in its annual report
     on Form 10-KSB for the year ended December 31, 1998.

          The financial statements, with the exception of the December 31, 1998
     balance sheet, are unaudited and have not been examined by independent
     certified public accountants.

(2)  Inventories
     -----------

          Inventories consist of the following:
<TABLE>
<CAPTION>
                                                                                                   March 31,            December 31,
                                                                                                     1999                   1998
                                                                                                 --------------         ------------

<S>                                                                                                  <C>                   <C>
            Raw materials                                                                            $ 723,423             $ 776,933
            Work in process                                                                            995,024             1,307,088
              Finished goods                                                                                --               170,022
                                                                                                 --------------         ------------
                                                                                                    $1,718,447            $2,254,043
                                                                                                 ==============         ============
</TABLE>

(3)  Earnings Per Share
     ------------------

          The reconciliation of the denominators of the basic and diluted
     earnings (loss) per share computations for the Company's reported earnings
     (loss) is as follows:
<TABLE>
<CAPTION>
                                                                                                               March 31,
                                                                                                 -----------------------------------
                                                                                                      1999                  1998
                                                                                                 --------------         ------------

<S>                                                                                                  <C>                   <C>
            Weighted average number of shares outstanding - basic                                    3,243,766             3,216,869
            Add net additional common shares upon exercise of common
                stock options                                                                               --               134,041
                                                                                                 --------------         ------------
            Adjusted weighted average common shares outstanding - diluted                            3,243,766             3,350,910
                                                                                                 ==============         ============
</TABLE>

(4)  Operating Segments and Related Information
     ------------------------------------------

          The following table presents certain operating division information in
     accordance with the provisions of SFAS No. 131, "Disclosure about Segments
     of an Enterprise and Related Information", which was adopted in 1998.
<TABLE>
<CAPTION>
                                                  Spire              Spire              Spire                             Total
                                                  Solar         Optoelectronics       Biomedical       All Other         Company
                                             ------------------------------------------------------------------------------------

     For the Three Months Ended March 31, 1999
     -----------------------------------------
     <S>                                       <C>                <C>                <C>              <C>             <C>
     Net sales and revenues                    $1,477,400         $1,289,938         $1,050,378       $       --      $ 3,817,716
     Earnings (loss) from operations             (159,132)           (28,918)            38,897               --         (122,354)
     Identifiable assets                        2,722,901          3,648,715          1,235,541        1,330,823        9,738,650
     Capital expenditures                          (5,163)            97,062             97,892          103,486          293,277
     Depreciation                                  38,250            136,691             76,349          251,290          502,580

     For the Three Months Ended March 31, 1998
     -----------------------------------------

     Net sales and revenues                    $1,336,640         $2,018,619         $1,087,267       $       --      $ 4,442,526
     Earnings (loss) from operations              (53,288)            66,042              4,404               --           13,822
     Identifiable assets                        3,159,162          4,890,245          2,073,240        2,473,550       12,596,205
     Capital expenditures                          37,654            204,386             52,044           72,547          366,631
     Depreciation                                  31,656            138,610             70,086          240,352          222,310
</TABLE>


                                       6
<PAGE>   7


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

OVERVIEW

     Spire develops, manufactures and markets highly-engineered photovoltaic
module manufacturing equipment and optoelectronic products and provides
biomedical processing services. Spire is the world's leader in the design and
manufacture of specialized equipment for the production of terrestrial
photovoltaic modules from solar cells, with its equipment installed in 142
factories and in 38 countries. The Company also offers certain optoelectronic
products and is continuing to develop additional advanced optoelectronic
products for telecommunications, biomedical and electronics applications.
Spire's value-added biomedical processing services offer surface treatments to
enhance the durability or antimicrobial characteristics of orthopedic and other
medical devices.

     The Company's net sales and revenues for the quarter ended March 31, 1999
declined, compared to the quarter ended March 31, 1998.

RESULTS OF OPERATIONS

     The following table sets forth certain items as a percentage of net sales
and revenues for the periods presented:

<TABLE>
<CAPTION>
                                                                                                    Three Months Ended March 31,
                                                                                                 -----------------------------------
                                                                                                      1999                  1998
                                                                                                 --------------         ------------

<S>                                                                                                  <C>                  <C>
       Net sales and revenues                                                                        100.0%               100.0%
       Cost of sales and revenues                                                                     73.9                 67.8
                                                                                                 --------------         ------------
       Gross profit                                                                                   26.1                 32.2
       Selling, general and administrative expenses                                                   29.3                 31.9
                                                                                                 --------------         ------------
       Earnings (loss) from operations                                                                (3.2)                 0.3
       Earnings (loss) before income taxes                                                            (3.9)                 0.6
       Income tax expense                                                                               --                  0.2
                                                                                                 --------------         ------------
       Net earnings (loss)                                                                            (3.9%)                0.4%
                                                                                                 ==============         ============
</TABLE>


QUARTER ENDED MARCH 31, 1999 COMPARED TO QUARTER ENDED MARCH 31, 1998

Net Sales and Revenues

     Net sales and revenues decreased $625,000 or 14% for the quarter ended
March 31, 1999 to $3,818,000, compared to $4,443,000 for the quarter ended March
31, 1998. Contract research, service and license revenues decreased $461,000 or
15% to $2,655,000 for the quarter ended March 31, 1999 compared to $3,116,000
for 1998. Manufacturing equipment sales decreased $164,000 or 12% to $1,163,000
for 1999, compared to $1,327,000 for 1998. The following table categorizes the
Company's net sales and revenues for the periods presented:
<TABLE>
<CAPTION>
                                                                                         Three Months Ended March 31,
                                                                         -----------------------------------------------------------
                                                                               1999                  1998                % Change
                                                                         --------------          --------------         ------------

<S>                                                                          <C>                   <C>                      <C>
       Contract research, service and license revenues                       $2,655,000            $3,116,000               (15%)
       Manufacturing equipment sales                                          1,163,000             1,327,000               (12%)
                                                                         --------------          --------------
       Net sales and revenues                                                $3,818,000            $4,443,000               (14%)
                                                                         ==============          ==============
</TABLE>

     The decline in manufacturing equipment sales for the three month period
ended March 31, 1999 is primarily due to a global decline in photovoltaic module
production. The decline in contract research, service and license revenues for
the three month period ended March 31, 1999 is primarily due to a decline in
both government and commercial contract research revenues.


                                       7
<PAGE>   8


Cost of Sales and Revenues

     The cost of sales and revenues decreased $189,000 to $2,822,000, but
increased to 74% of net sales and revenues, for the quarter ended March 31,
1999, compared to $3,011,000 or 68% of net sales and revenues for the quarter
ended March 31, 1998.

     The cost of contract research, service and license revenues decreased
$391,000 to $1,816,000, and decreased to 68% of related revenues, for the
quarter ended March 31, 1999, compared to $2,207,000 or 71% of related revenues
for the quarter ended March 31, 1998. The decline is due to cost reduction steps
the Company undertook in 1998 and 1999. Cost of manufacturing equipment sales
increased $202,000 to $1,006,000, and increased to 87% of related sales, for the
quarter ended March 31, 1999, compared to $804,000 or 61% of related sales, for
the quarter ended March 31, 1998. Cost of manufacturing equipment sales
increased due to a decrease in sales volume which resulted in an
underutilization of fixed costs.

     The following table categorizes the Company's cost of sales and revenues
for the periods presented, stated in dollars and as a percentage of related
sales and revenues:
<TABLE>
<CAPTION>
                                                                                         Three Months Ended March 31,
                                                                         -----------------------------------------------------------
                                                                              1999              %               1998            %
                                                                         --------------      --------      --------------    -------

<S>                                                                         <C>                 <C>            <C>             <C>
       Contract research, service and license revenues                      $1,816,000          68%            $2,207,000      71%
       Manufacturing equipment sales                                         1,006,000          87%               804,000      61%
                                                                         --------------                    --------------
       Total cost of sales and revenues                                     $2,822,000          74%            $3,011,000      68%
                                                                         ==============                    ==============
</TABLE>

Selling, General and Administrative Expenses

     Selling, general and administrative expenses for the three months ended
March 31, 1999 decreased $300,000 to $1,118,000, and decreased to 29% of sales
and revenues, compared to $1,418,000 or 32% of sales and revenues for the three
months ended March 31, 1998, primarily due to cost reductions implemented by the
Company in 1998 and 1999.

Depreciation and Amortization Expenses

     Depreciation and amortization expenses for the three months ended March 31,
1999 increased $12,000 or 5% to $251,000, compared to $239,000 for the three
months ended March 31, 1998. Capital expenditures decreased $74,000 or 20% to
$293,000 for the three months ended March 31, 1999, compared to $367,000 for the
three months ended March 31, 1998.

Interest

     The Company earned $3,000 in interest income for the quarter ended March
31, 1999, compared to $13,000 for the quarter ended March 31, 1998. The Company
incurred interest expense of $30,000 in the first quarter of 1999, primarily due
to its borrowings under a revolving line of credit. The Company incurred
insignificant interest expense for the quarter ended March 31, 1998.

Income Taxes

     The Company recorded no income tax expense or benefit for the three months
ended March 31, 1999 and income tax expense of $9,000 for the three months ended
March 31, 1998.

Net Earnings (Loss)

     The Company reported a net loss for the quarter ended March 31, 1999 of
$149,000, compared to net earnings of $17,000 for the quarter ended March 31,
1998. The decline in the Company's profitability resulted from a decrease in net
sales and revenues when compared with the prior period, partially offset by cost
reductions implemented by the Company in 1998.


                                       8
<PAGE>   9


LIQUIDITY AND CAPITAL RESOURCES

     To date the Company has been able to fund its liquidity requirements using
cash from operations and available lines of credit. On March 19, 1999, the
Company amended and extended its revolving credit agreement with Silicon Valley
Bank. This agreement provides for a $2 million revolving credit facility, based
upon eligible accounts receivable requirements. This line of credit has been
established to provide the Company with resources for general working capital
purposes and Standby Letter of Credit Guarantees for foreign customers. The line
is secured by all assets of the Company. Interest on the line is at the Bank's
prime rate plus one percent. The line contains covenants including provisions
relating to profitability and net worth. The Company is in compliance with these
covenants at March 31, 1999. As of March 31, 1999, the Company had $550,000
outstanding debt under this revolving credit facility.

     Cash and cash equivalents decreased $25,000 to $97,000 at March 31, 1999,
from $122,000 at December 31, 1998. To date there are no material commitments by
the Company for capital expenditures. At March 31, 1999, the Company's
accumulated deficit was $2,328,000, compared to an accumulated deficit of
$2,179,000 as of December 31, 1998. Working capital as of March 31, 1999
decreased 14% to $1,287,000, compared to $1,501,000 as of December 31, 1998.
Although no assurances can be made, the Company expects that cash flow from
operations, the existing line of credit with its bank, and available lease
arrangements, will be sufficient to meet its needs for working capital. However,
the Company believes it has insufficient capital resources for business
expansion. The Company has taken steps to conserve its resources by reducing its
cost of operations. In addition, the Company is exploring ways to increase
capital through possible increased debt, equity, or sale of part or all of the
Company. The Company has engaged the investment banking firms of Laird & Company
and OEM Capital to assist in this endeavor.

RECENT ACCOUNTING PRONOUNCEMENTS

     In June 1998, the Financial Accounting Standards Board issued SFAS 133,
"Accounting for Derivative Instruments and Hedging Activities", which
establishes accounting and reporting standards for derivative instruments,
including certain derivative instruments embedded in other contracts
(collectively referred to as "derivatives") and for hedging activities. This
statement requires that an entity recognize all derivatives as either assets or
liabilities in the balance sheet and measure those instruments at fair value.
The statement also sets forth the criteria for determining whether a derivative
may be specifically designed as a hedge of a particular exposure with the intent
of measuring the effectiveness of that hedge in the statement of operations.
SFAS 133 is effective for all fiscal quarters of fiscal years beginning after
June 15, 1999. Management does not believe that the adoption of this statement
will have a material impact on the Company's consolidated financial position,
results of operations or cash flows.

IMPACT OF INFLATION AND CHANGING PRICES

     Historically, the Company's business has not been materially impacted by
inflation. Manufacturing equipment sales are generally quoted, manufactured and
shipped within a cycle of approximately six months, allowing for orderly pricing
adjustments to the cost of labor and purchased parts. The Company has not
experienced any negative effects from the impact of inflation on long-term
contracts. The Company's service business is not expected to be seriously
affected by inflation because its procurement-production cycle typically ranges
from two weeks to several months, and prices generally are not fixed for more
than one year. Research and development contracts usually include cost
escalation provisions.

FOREIGN EXCHANGE FLUCTUATION

     The Company sells only in U.S. dollars, generally against an irrevocable
confirmed letter of credit through a major U.S. bank. Therefore the Company is
not directly affected by foreign exchange fluctuations on its current orders.
However, fluctuations in foreign exchange rates do have an effect on the
Company's customers' access to U.S. dollars and on the pricing competition on
certain pieces of equipment that the Company sells in selected markets.


                                       9
<PAGE>   10


IMPACT OF THE YEAR 2000 ISSUE

     The Company has identified the potential impact of the Year 2000 issue. The
Year 2000 issue relates to computer programs and embedded computer chips being
viable to distinguish between the year 1900 and the year 2000.

     The Company has completed a review and assessment of potentially affected
items, including information technology and non-information technology, for Year
2000 compliance. When identifying computer programs that were not Year 2000
compliant, the Company sought to upgrade these programs to newer versions of
software that are Year 2000 compliant. The Company's main business system's
upgrade to Y2K compliant software has been installed. Data files will be
converted during the second quarter of 1999. The Company's manufacturing package
upgrade has been ordered, and should be installed during the second quarter of
1999. The Company estimates that it will obtain all remaining required software
no later than June 1999. The cost of the software is estimated to not exceed
$50,000.

     The Company's business is also dependent upon systems of third parties,
primarily its vendors and customers. The Company has submitted questionnaires to
all of its significant vendors. The Company is now collecting and analyzing
their responses. Although this process is incomplete, no known problems have
been identified. The Company expects to complete the analysis by June 1999. The
Company issued questionnaires to its customer base. The Company anticipates
completion of the analysis of its customer base by June 1999.

     The Company believes that its most likely and reasonable worst case
scenario relating to the Year 2000 would be failure of certain of its
applications with imbedded software or failure of such applications of a
material customer or vendor. Failure of applications of embedded software could
result in a disruption of the Company's operation and thereby negatively affect
revenues and profitability. Failure of a significant vendor's information
systems could temporarily interrupt supply of materials or services and impair
the Company's ability to fill orders. If a major customer system fails to become
Year 2000 compliant, the Company's revenues could be temporarily disrupted if
the customer suspends further purchases. Although there can be no assurance that
these failures will not have an adverse effect on the Company's business, the
Company believes that any such adverse effect would not be material.

     The Company is formulating contingency plans to address any such failures.
The plans include identifying Year 2000 compliant software for the Company's
internal systems, and identifying alternative vendors to assure continuity of
supplies.

     THE FOREGOING STATEMENTS MAY INCLUDE FORWARD-LOOKING STATEMENTS SUBJECT TO
RISKS AND UNCERTAINTIES THAT COULD CAUSE ACTUAL RESULTS TO DIFFER MATERIALLY
FROM THOSE INDICATED IN THE FORWARD-LOOKING STATEMENTS. FACTORS THAT MIGHT CAUSE
SUCH A DIFFERENCE INCLUDE, BUT ARE NOT LIMITED TO, THOSE DISCUSSED OR REFERRED
TO IN THIS REPORT AND IN ITEM 6 OF THE ANNUAL REPORT ON FORM 10-KSB FOR THE YEAR
ENDED DECEMBER 31, 1998.

PART II - OTHER INFORMATION
---------------------------

ITEM 1.  LEGAL PROCEEDINGS
--------------------------

     The Company is subject, from time to time, to legal proceedings and claims
arising out of its business, which cover a wide range of matters. Management,
after review and consultation with counsel, considers that any liability from
all of these legal proceedings and claims would not materially affect the
consolidated financial position, results of operations or liquidity of the
Company.

ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K
-----------------------------------------

A.   The following exhibits are filed herewith:

     27    Financial Data Schedule

B.   During the quarter ended March 31, 1999, the Company filed no reports on
     Form 8-K.


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                                   SIGNATURES


In accordance with the requirements of the Exchange Act, the registrant caused
this report to be signed on its behalf by the undersigned, thereunto duly
authorized.


                                          SPIRE CORPORATION
                                          (Registrant)


  14 May 1999                             By: /s/ Roger G. Little
------------------------                      ----------------------------------
Date                                          Roger G. Little
                                              President, Chief Executive Officer
                                              and Chairman of the Board


  14 May 1999                             By: /s/ Richard S. Gregorio
-----------------------                       ----------------------------------
Date                                          Richard S. Gregorio
                                              Vice President and Chief Financial
                                              Officer, Treasurer, Clerk and
                                              Principal Accounting Officer


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