EXHIBIT 32.1 CERTIFICATIONS OF CHIEF EXECUTIVE OFFICER, CHIEF FINANCIAL OFFICER AND CHIEF ACCOUNTING OFFICER PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002 In connection with the Quarterly Report of GTJ REIT, Inc. (the "Company") on Form 10-Q for the quarter ended September 30, 2007 as filed with the Securities and Exchange Commission on the date hereof (the "Periodic Report"), I, Jerome Cooper, President and Chief Executive Officer and I, Michael Kessman, Chief Accounting of the registrant, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that: 1. the Periodic Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and 2. the information contained in the Periodic Report fairly presents, in all material respects, the financial condition and results of operations of the Company. Dated: March 18, 2008 /s/ Jerome Cooper ------------------------------------- Jerome Cooper President and Chief Executive Officer Date: March 18, 2008 /s/ Michael I. Kessman ------------------------------------- Michael I. Kessman Chief Accounting Officer