UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q/A

(Amendment No. 1)

FOR THE QUARTERLY PERIOD ENDED JANUARY 28, 2012.

Commission File No. 0-20572

PATTERSON COMPANIES, INC.

(Exact name of registrant as specified in its charter)

(651) 686-1600

(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, 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.

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

Patterson Companies, Inc. had outstanding 110,973,887 shares of common stock as of March 2, 2012.

EXPLANATORY NOTE

This Amendment No. 1 to the Quarterly Report on Form 10-Q (the “Form 10-Q”) of Patterson Companies, Inc. for the period ended January 28, 2012 is being filed solely (i) to furnish Exhibit 101 to the Form 10-Q in accordance with Rule 405 of Regulation S-T . Exhibit 101 to the Form 10-Q provides the consolidated financial statements and related notes from the Form 10-Q formatted in XBRL (eXtensible Business Reporting Language).

Pursuant to Rule 12b-15 under the Securities Exchange Act of 1934, as amended, this Form 10-Q/A also contains new certifications pursuant to Section 302 of the Sarbanes-Oxley Act of 2002, which are attached hereto. Because no financial statements have been included in this Form 10-Q/A and this Form 10-Q/A does not contain or amend any disclosure with respect to Items 307 and 308 of Regulation S-K, paragraphs 3, 4, and 5 of the certifications have been omitted.

No other changes have been made to the Form 10-Q. This Amendment No. 1 to the Form 10-Q speaks as of the original filing date of the Form 10-Q, does not reflect events that may have occurred subsequent to the original filing date, and does not modify or update in any way disclosures made in the original Form 10-Q.

Pursuant to Rule 406T of Regulation S-T, the interactive data files on Exhibit 101 hereto are deemed not filed or part of a registration statement or prospectus for purposes of Sections 11 or 12 of the Securities Act of 1933, as amended, are deemed not filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, and otherwise are not subject to liability under those sections.

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PART II—OTHER INFORMATION

ITEM 6. EXHIBITS

See Exhibit Index

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SIGNATURE

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.

EXHIBIT INDEX