EXHIBIT - 99.906CERT

                           Section 906 Certifications

We, Peter E. Sundman,  Chief Executive Officer and Barbara Muinos,  Treasurer of
Neuberger Berman Real Estate Securities Income Fund Inc. (the "Fund"),  certify,
pursuant  to  18  U.S.C.   Section  1350  enacted   under  Section  906  of  the
Sarbanes-Oxley Act of 2002, that to my knowledge:

     1.   The Fund's  periodic  report on Form N-CSR for the period ended August
          31, 2003 fully  complies  with the  requirements  of Section  13(a) or
          15(d) of the Securities Exchange Act of 1934 (15 U.S.C. Section 78m(a)
          or 78o(d); and

     2.   The information  contained in such Form N-CSR fairly presents,  in all
          material respects,  the financial  condition and results of operations
          of the Fund.

Date:  December 31, 2003


                                      /s/ Peter E. Sundman
                                      ----------------------
                                      Peter E. Sundman
                                      Chief Executive Officer


Date:  January 8, 2004


                                      /s/ Barbara Muinos
                                      ----------------------
                                      Barbara Muinos
                                      Treasurer and Principal Financial
                                      and Accounting Officer

A signed  original of this written  statement  required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature that
appears in typed form within the  electronic  version of this written  statement
required by 906, has been  provided to the Fund and will be retained by the Fund
and  furnished  to the  Securities  and  Exchange  Commission  or its staff upon
request.

This  certification  is being furnished to the Commission  solely pursuant to 18
U.S.C.  ss.  1350 and is not  being  filed as part of the  Form  N-CSR  with the
Commission.