Exhibit 31.2


                    CHIEF FINANCIAL OFFICER'S CERTIFICATION



I, Gerald Luterman, certify that:

     1. I have reviewed this annual report on Form 10-K of KeySpan Corporation;

     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
registrant as of, and for, the periods presented in this annual report;

     4. The  registrant's  other  certifying  officer and I are  responsible for
establishing and maintaining  disclosure  controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal  control over financial
reporting  (as defined in Exchange Act Rules  13a-15(f) and  15d-15(f))  for the
registrant and have:

     a)  Designed  such  disclosure  controls  and  procedures,  or caused  such
disclosure  controls and  procedures to be designed  under our  supervision,  to
ensure that  material  information  relating to the  registrant,  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) Designed such internal control over financial reporting,  or caused such
internal control over financial  reporting to be designed under our supervision,
to provide reasonable assurance regarding the reliability of financial reporting
and the preparation of financial  statements for external purposes in accordance
with generally accepted accounting principals;

     c) Evaluated the effectiveness of the registrant's  disclosure controls and
procedures and presented in this report our conclusions  about the effectiveness
of the disclosure  controls and procedures,  as of the end of the period covered
by this report based on such evaluation; and

     d) Disclosed in this report any change in the registrant's internal control
over  financial  reporting  that occurred  during the  registrant's  most recent
fiscal quarter (the registrant's  fourth fiscal quarter in the case of an annual
report) that has  materially  affected,  or is  reasonably  likely to materially
affect, the registrant's internal control over financial reporting; and

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

     a) all significant  deficiencies  and material  weaknesses in the design or
operation of internal  control over  financial  reporting  which are  reasonably
likely  to  adversely  affect  the  registrant's  ability  to  record,  process,
summarize and report financial information; and

     b) any fraud,  whether or not material,  that involves  management or other
employees who have a significant role in the registrant's  internal control over
financial reporting.



Date: March 1, 2005


                                                 /s/Gerald Luterman
                                                 ---------------------
                                                 Gerald Luterman
                                                 Executive Vice President
                                                 and Chief Financial Officer







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