UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported) July 5, 2012

Fiesta Restaurant Group, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (315) 424-0513

N/A

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

ITEM 5.02. DEPARTURE OF DIRECTORS OR CERTAIN OFFICERS; ELECTION OF DIRECTORS; APPOINTMENT OF CERTAIN OFFICERS; COMPENSATORY ARRANGEMENTS OF CERTAIN OFFICERS.

On July 5, 2012, Barry J. Alperin was appointed a Class II member of the Board of Directors of Fiesta Restaurant Group, Inc. (the “Company”). Mr. Alperin, who is retired, served as Vice Chairman of Hasbro, Inc. from 1990 through 1995, as Co-Chief Operating Officer of Hasbro from 1989 through 1990 and as Senior Vice President or Executive Vice President of Hasbro from 1985 through 1989. He was a director of Hasbro from 1985 through 1996. Prior to joining Hasbro, Mr. Alperin practiced law in New York City for 20 years, dealing with corporate, public and private financial transactions, corporate mergers and acquisitions, compensation issues and securities law matters. Mr. Alperin currently serves as a director of The Hain Celestial Group, Inc. (and is Chairman of its corporate governance and nominating committee and a member of its audit committee), Henry Schein, Inc. (and is Chairman of its compensation committee and a member of its audit committee and nominating and governance committee) and is a director of two privately held corporations, K’NEX Industries, Inc., a toy manufacturer, and Weeks Marine, Inc., a marine construction company. During the past five years, Mr. Alperin served on the Board of Directors of K-Sea Transportation Partners L.P. He serves as a trustee and member of the Executive Committee of The Caramoor Center for Music and the Arts, President Emeritus and a Life Trustee of The Jewish Museum in New York City and is a past President of the New York Chapter of the American Jewish Committee where he also served as Chair of the audit committee of the national organization. Mr. Alperin also formerly served as Chairman of the Board of Advisors of the Tucker Foundation at Dartmouth College, was President of the Board of the Stanley Isaacs Neighborhood Center in New York City, was a trustee of the Hasbro Children’s Foundation, was President of the Toy Industry Association and was a member of the Columbia University Medical School Health Sciences Advisory Council.

Mr. Alperin’s financial expertise, his extensive experience in corporate and securities laws and corporate governance matters and his service on the boards of directors of several public companies brings significant leadership, management, operational and financial experience to the Company’s Board of Directors.

Mr. Alperin serves on the Company’s Audit Committee and the Corporate Governance and Nominating Committee.

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Signatures

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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