As filed with the Securities and Exchange Commission on November 4, 2010

Registration No. 333-168736

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Triangle Petroleum Corporation

(Exact name of registrant as specified in its charter)

1625 Broadway, Suite 780

Denver, CO 80202

(303) 260-7125

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Peter J. Hill

President and Chief Executive Officer

Triangle Petroleum Corporation

1625 Broadway, Suite 780

Denver, CO 80202

(303) 260-7125

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Approximate date of commencement of proposed sale to the public: As soon as practicable after the effective date of this registration statement.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 check the following box.    ¨

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    x  File No. 333-168736

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    ¨

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 the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

CALCULATION OF REGISTRATION FEE

This registration statement shall become effective upon filing with the Commission in accordance with Rule 462(b) under the Securities Act.

EXPLANATORY NOTE

This registration statement is being filed pursuant to Rule 462(b) (“Rule 462(b)”) under the Securities Act of 1933, as amended, and General Instruction V of Form S-1. Pursuant to Rule 462(b), the contents of our registration statement on Form S-1, as amended (File No. 333-168736), including the exhibits thereto, which was declared effective by the Securities and Exchange Commission (the “Commission”) on November 4, 2010 (the “Initial Registration Statement”), are incorporated by reference into this registration statement. This registration statement covers the registration of an additional 2,070,000 shares of our common stock in the offering related to the Initial Registration Statement.

We hereby certify to the Commission that we (i) have instructed our bank to transmit to the Commission the filing fee set forth on the cover page of this registration statement by a wire transfer of such amount to the Commission’s account as soon as practicable (but not later than the close of business on November 5, 2010), (ii) will not revoke such instructions, (iii) have sufficient funds in the relevant account to cover the amount of such filing fee and (iv) will confirm receipt of such instructions by our bank during the bank’s regular business hours on November 5, 2010.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

EXHIBIT INDEX

II-1

Signatures

Pursuant to the requirements of the Securities Act, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Denver, Colorado, on the 4^th day of November, 2010.

Pursuant to the requirements of the Securities Act, as amended, this registration statement has been signed below by the following persons in the capacities and on the dates indicated.

Signatures

Pursuant to the requirements of the Securities Act, this registration statement has been signed by the following persons in the capacities indicated on.

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