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 Report on Form 10-Q for the period ended June 30, 2006
     of KeySpan Corporation;

2.   Based on my knowledge, this 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
     report;

3.   Based on my  knowledge,  the  financial  statements,  and  other  financial
     information  included  in  this  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 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 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:    August 3, 2006


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














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