EXHIBIT 99(B)
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                                 CERTIFICATIONS


       I, Gregory G. Towle, Financial Controller, Treasurer, and Principal
Financial and Accounting Officer of Spire Corporation (the "Company"), certify
that:

       1. I have reviewed this annual report on Form 10-KSB of the Company.

       2. Based on my knowledge, this annual report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this annual
report.

       3. Based on my knowledge, the financial statements, and other financial
information included in this annual report, fairly present in all material
respects the financial condition, results of operations and cash flows of the
Company as of, and for, the periods presented in this annual report.

       4. The Company's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-14 and 15d-14) for the Company and have:

           a) Designed such disclosure controls and procedures to ensure that
material information relating to the Company, including its consolidated
subsidiaries, is made known to us by others within those entities, particularly
during the period in which this annual report is being prepared;

           b) Evaluated the effectiveness of the Company's disclosure controls
and procedures as of a date within 90 days prior to the filing date of this
annual report (the "Evaluation Date"); and

           c) Presented in this annual report our conclusions about the
effectiveness of the disclosure controls and procedures based on our evaluation
as of the Evaluation Date.

       5. The Company's other certifying officer and I have disclosed, based on
our most recent evaluation, to the Company's auditors and the audit committee of
the Company's board of directors (or persons performing the equivalent
functions):

           a) All significant deficiencies in the design or operation of
internal controls which could adversely affect the Company's ability to record,
process, summarize and report financial data and have identified for the
Company's auditors any material weaknesses in internal controls; and

           b) Any fraud, whether or not material, that involves management or
other employees who have a significant role in the Company's internal controls.

       6. The Company's other certifying officer and I have indicated in this
annual report whether or not there were significant changes in internal controls
or in other factors that could significantly affect internal controls subsequent
to the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.

Dated:  April 9, 2003             By: /s/ Gregory G. Towle
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                                      Financial Controller, Treasurer, and
                                      Principal Financial and Accounting Officer