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): March 23, 2012

MULTI-FINELINE ELECTRONIX, INC.

(Exact name of registrant as specified in its charter)

3140 East Coronado Street

Anaheim, CA 92806

(Address of principal executive offices) (Zip Code)

(714) 688-5201

(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 1.01 Entry into a Material Definitive Agreement

On March 23, 2012, MFLEX Chengdu Co., Ltd. (“MCH”), a subsidiary of Multi-Fineline Electronix, Inc., entered into a Line of Credit Agreement (the “MCH Credit Line”) with Bank of China Co., Ltd. Chengdu Development West Zone Sub-Branch (“BC”), providing for a line of credit to MCH in an amount of $11 million US dollars. The MCH Credit Line will mature on October 17, 2012. MCH and BC have also entered into a Facility Offer Letter dated as of March 23, 2012 (the “Facility Offer Letter”). The Facility Offer Letter sets forth basic pricing and favorable pricing (the “MFLEX Price”) negotiated by BC and MCH. The loan interest rate for US dollar borrowing under the MCH Credit Line shall not be lower than the one-year LIBOR rate plus 550 basis points. The basis points shall be negotiated by the parties based on the lending cost in the Chinese market for US dollars on the day the loan is made. A copy of each of the MCH Credit Line and the Facility Offer Letter are attached hereto.

Item 9.01. Financial Statements and Exhibits

(d) Exhibits

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SIGNATURE

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, thereunto duly authorized.

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EXHIBIT INDEX

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