UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-Q/A

(Amendment No. 1)

For the Quarterly Period Ended March 31, 2011

OR

Commission File Number 000-54374

RENEWABLE ENERGY GROUP, INC.

(Exact name of registrant as specified in its charter)

416 South Bell Avenue Ames, Iowa 50010

(Address of principal executive offices)

(515) 239-8000

(Registrant’s telephone number, including area code)

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 Web site, if any, every Interactive Data file required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§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, non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act:

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

As of April 30, 2011, there was no public trading market for the Company’s common stock. There were 33,129,553 shares of the Company’s common stock and 13,455,522 shares of the Company’s preferred stock outstanding on April 30, 2011.

Explanatory Note

Renewable Energy Group, Inc. (the “Company”) is filing this Amendment No. 1 to its Form 10-Q originally filed with the Securities and Exchange Commission on May 16, 2011 (the “Original Filing”). This Amendment is being filed solely for the purpose of correcting the certifications filed as Exhibits 31.1 and 31.2 to the Original Filing, each of which inadvertently omitted paragraph 4(b).

(A) Exhibits:

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Dated: August 25, 2011