UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 10-K/A

(Amendment No. 1)

(Mark One)

For the fiscal year ended June 30, 2009

OR

For the transition period from            to            

Commission File No. 0-28032

PATAPSCO BANCORP, INC.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (410) 285-1010

Securities registered pursuant to Section 12(b) of the Act: None

Securities registered pursuant to Section 12(g) of the Act:

Common stock, par value $.01 per share

(Title of Class)

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ¨    No  x

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act.    Yes  ¨    No  x

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 during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  ¨    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  ¨

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):

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 December 31, 2008, the aggregate market value of voting common stock held by nonaffiliates was approximately $5,735,447, computed by reference to the closing sales price on December 31, 2008 as reported on the OTC Electronic Bulletin Board.

Number of shares of Common Stock outstanding as of September 22, 2009: 1,874,734.

DOCUMENTS INCORPORATED BY REFERENCE

1. Portions of the 2009 Annual Report to Stockholders. (Part II)

2. Portions of the Proxy Statement for the 2009 Annual Meeting of Stockholders. (Part III)

EXPLANATORY NOTE

This Amendment No. 1 to Annual Report on Form 10-K/A for the fiscal year ended June 30, 2009 of Patapsco Bancorp, Inc. is being filed to include Exhibit 99.1, “31 C.F.R. § 30.15 Certification of Chief Executive Officer” and Exhibit 99.2, “31 C.F.R. § 30.15 Certification of Chief Financial Officer.”

PART IV

(1) Financial Statements. The following consolidated financial statements are incorporated by reference from Item 7 hereof (see Exhibit 13 to this Annual Report on Form 10-K):

Report of Registered Independent Accounting Firm

Consolidated Statements of Financial Condition as of June 30, 2009 and 2008

Consolidated Statements of Income for the Years Ended June 30, 2009 and 2008

Consolidated Statements of Stockholders’ Equity for the Years Ended June 30, 2009 and 2008

Consolidated Statements of Cash Flows for the Years Ended June 30, 2009 and 2008

Notes to Consolidated Financial Statements

(2) Exhibits. The following is a list of exhibits filed as part of this Annual Report on Form 10-K and also constitutes the Exhibit Index.

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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.