Exhibit 31.2

                              CERTIFICATION OF THE

              EXECUTIVE VICE PRESIDENT AND CHIEF FINANCIAL OFFICER

                             PURSUANT TO SECTION 302

                        OF THE SARBANES-OXLEY ACT OF 2002


         I, Gerald Luterman, certify that:

     1. I have reviewed this Quarterly  Report on Form 10-Q for the period ended
June 30, 2005 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:   June 30, 2005


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


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