UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q/A

(Amendment No. 1)

(Mark One)

For the Quarterly Period Ended June 28, 2011

OR

For the transition period from             to             

Commission file number 0-21423

BJ’S RESTAURANTS, INC.

(Exact name of registrant as specified in its charter)

7755 Center Avenue

Suite 300

Huntington Beach, California 92647

(714) 500-2400

(Address, including zip code, and telephone number, including

area code, of registrant’s principal executive offices)

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every interactive data file required to be submitted and posted pursuant to Rule 405 of Regulation S-T (section 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  x    No  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definition of “accelerated filer,” “large accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).    Yes  ¨    No  x.

As of July 29, 2011, there were 27,698,012 shares of Common Stock of the Registrant outstanding.

EXPLANATORY NOTE

This Form 10-Q/A amends the quarterly report on Form 10-Q of BJ’s Restaurants, Inc. (the “Company”) for the quarter ended June 28, 2011 (the “Original Filing”), filed on August 3, 2011, to include additional information regarding the Company’s late filing of its proxy statement in 2010 and 2011. The remainder of the Original Filing remains unchanged.

This Form 10-Q/A amends Part I, Item 4 (Controls and Procedures) in the Company’s Original Filing. Except to the extent required to reflect the above-referenced revisions, this Form 10-Q/A continues to describe the Company as of the date of the Original Filing, and does not update disclosures to reflect events that occurred after the date of the Original Filing. Accordingly, this amendment should be read in conjunction with the Original Filing and with our other filings made with the Securities and Exchange Commission subsequent to the filing of the Original Filing, including any amendments to those filings.

Item 4. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

Under the supervision and with the participation of our management, including the Chief Executive Officer and Chief Financial Officer, we have evaluated the effectiveness of our disclosure controls and procedures pursuant to Rules 13a-15 and 15d-15 promulgated under the Securities Exchange Act of 1934 as amended, as of the end of the period covered by this report. Based on that evaluation, the Chief Executive Officer and Chief Financial Officer have concluded that these disclosure controls and procedures are effective.

In 2010 and in 2011, we failed to timely file our proxy statement within the 120 day period following fiscal year-end to properly incorporate certain information by reference into our Annual Report on Form 10-K. The definitive 2010 proxy statement was filed on May 3, 2010 (three business days after the due date). The late 2010 proxy statement filing was a result of a change in the agenda for the annual meeting to include a proposal that required us to file a preliminary proxy statement. We had filed a preliminary proxy statement on April 21, 2010. However, because the 10-day waiting period required by Rule 14a-6 had not elapsed, we waited until May 3, 2010 to file the definitive proxy statement, owing to an internal miscalculation of the required filing date for our preliminary proxy statement. The 2011 proxy statement was filed on May 6, 2011 (seven business days after applicable due date), due to external securities counsel miscalculating the due date. In each case, the failure to timely file was not a result of any failure in our ability to gather accurate information or draft the relevant disclosures within the time periods required under the Exchange Act. As a result, we determined that the causes of each untimely filing were unrelated and not indicative of a pattern or systemic deficiency in our overall disclosure controls and procedures.

Changes in Internal Control Over Financial Reporting

There has not been any change in our internal control over financial reporting (as such term is defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) during our second fiscal quarter that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

Item 6. EXHIBITS

SIGNATURES

In accordance with the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this Amendment No. 1 to be signed on its behalf by the undersigned, thereunto duly authorized.