RECKSON OPERATING PARTNERSHIP, L. P.
                                  EXHIBIT 32.1
    CERTIFICATION OF SCOTT H. RECHLER, CHAIRMAN OF THE BOARD, CHIEF EXECUTIVE
  OFFICER, PRESIDENT AND DIRECTOR OF RECKSON ASSOCIATES REALTY CORP., THE SOLE
  GENERAL PARTNER OF THE REGISTRANT, PURSUANT TO SECTION 1350 OF CHAPTER 63 OF
                       TITLE 18 OF THE UNITED STATES CODE


I, Scott H. Rechler, Chairman of the Board, Chief Executive Officer, President
and Director of Reckson Associates Realty Corp., the sole general partner of
Reckson Operating Partnership, L. P. (the "Company"), certify pursuant to
Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that:

         1)  The Quarterly Report on Form 10-Q of the Company for the quarterly
             period ended June 30, 2005 (the "Report") fully complies with the
             requirements of Section 13(a) or 15(d) of the Securities Exchange
             Act of 1934 (15 U.S.C. 78m or 78o(d)); and

         2)  The information contained in the Report fairly presents, in all
             material respects, the financial condition and results of
             operations of the Company.


Dated: August 8, 2005
                                 By /s/ Scott H. Rechler
                                    ------------------------------------------
                                 Scott H. Rechler,
                                 Chairman of the Board, Chief Executive Officer,
                                 President and Director of Reckson Associates
                                 Realty Corp., the sole general partner of the
                                 Registrant


A signed original of this written statement required by Section 906 has been
provided to Reckson Operating Partnership, L.P. and will be furnished to the
Securities and Exchange Commission or its staff upon request.