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) December 10, 2014

DIODES INCORPORATED

(Exact name of registrant as specified in its charter)

(972) 987-3900

(Registrant’s telephone number, including area code)

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 7.01. Regulation FD Disclosure.

On December 10, 2014, Diodes Incorporated issued a press release updating its guidance for the fourth quarter of 2014. A copy of the press release is furnished as Exhibit 99.1 and incorporated herein by reference.

The information in this Item 7.01, including Exhibit 99.1, will not be treated as filed for the purposes of Section 18 of the Securities Exchange Act of 1934 (the “Exchange Act”) or otherwise subject to the liabilities of that section. This information will not be incorporated by reference into a filing under the Securities Act of 1933, or into another filing under the Exchange Act, unless that filing expressly refers to specific information in this Form 8-K. The furnishing of the information in this Item 7.01 is not intended to, and does not, constitute a representation that such furnishing is required by Regulation FD or that the information in this Item 7.01 is material information that is not otherwise publicly available. This Regulation FD disclosure constitutes a forward-looking statement intended to be within the protection for such statements under the Private Securities Litigation Reform Act of 1995. For an explanation of the risks that could cause the actual results to differ from those in this forward-looking statement, please see the Safe Harbor Statement accompanying the press release included as Exhibit 99.1.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

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.