UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): August 7, 2013

ORION ENERGY SYSTEMS, INC.

(Exact name of registrant as specified in its charter)

2210 Woodland Drive, Manitowoc, Wisconsin

(Address of principal executive offices, including zip code)

(920) 892-9340

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Item 5.07(a) and (b)    Submission of Matters to a Vote of Security Holders.

On August 7, 2013, Orion Energy Systems, Inc. (the “Company”) held its 2013 annual meeting of shareholders. As of the June 4, 2013 record date for the determination of the shareholders entitled to notice of, and to vote at, the annual meeting, 20,177,922 shares of common stock were outstanding and entitled to vote, each entitled to one vote per share. Approximately 79.4% of all votes were represented at the annual meeting in person or by proxy. At the annual meeting, the Company’s shareholders voted on the following proposals:

Proposal One: To elect three Class III directors, James R. Kackley, James D. Leslie and Thomas N. Schueller, to serve until the 2016 annual meeting of shareholders and to elect one Class I director, Kenneth L. Goodson, Jr., to serve until the 2014 annual meeting of shareholders and, in each instance, until their successors are duly elected and qualified. In accordance with the voting results listed below, each of the nominees were elected to serve as directors.

Proposal Two: To conduct an advisory vote to approve the compensation of the Company’s named executive officers as disclosed in the Company’s Definitive Proxy Statement. In accordance with the voting results listed below, the Company’s executive compensation as disclosed in the Company’s Definitive Proxy Statement has been approved.

Proposal Three: To ratify BDO USA, LLP to serve as the Company’s independent registered public accounting firm for fiscal year 2014. In accordance with the voting results listed below, BDO USA, LLP will serve as the independent registered certified public accountants for fiscal 2014.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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