UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 OR 15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of October 2013

Commission File Number 000-51138

GRAVITY CO., LTD.

(Translation of registrant’s name into English)

Nuritkum Square Business Tower 15F, 1605 Sangam-Dong, Mapo-Gu, Seoul, Korea 121-795

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.  Form 20-F x Form 40-F o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): o

ENGAGEMENT OF REGISTRANT’S CERTIFYING ACCOUNTANT

Seoul, South Korea — October 11, 2013 — GRAVITY Co., Ltd. (NasdaqGM: GRVY) (“Gravity” or the “Company”), an online game developer and publisher based in South Korea, is furnishing this current report on Form 6-K to report that on October 11, 2013, the audit committee of the Company decided to engage Deloitte Anjin LLC (“Deloitte”), the Korean member firm of Deloitte Touche Tohmatsu Limited, as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2013 for its financial statements in conformity with generally accepted accounting principles in the United States of America.

During the Company’s fiscal years ended December 31, 2011 and December 31, 2012 and through the subsequent interim period on or prior to October 11, 2013, neither the Company nor anyone on its behalf consulted with Deloitte on either (i) the application of accounting principles to a specified transaction, either completed or proposed, or the type of audit opinion that might be rendered on the Company’s financial statements, and neither a written report nor oral advice was provided to the Company that Deloitte concluded was an important factor considered by the Company in reaching a decision as to any accounting, auditing or financial reporting issue; or (ii) any matter that was either the subject of a disagreement, as that term is defined in Item 16F(a)(1)(iv) of Form 20-F (and the related instructions thereto), or a reportable event as set forth in Item 16F(a)(1)(v) of Form 20-F.

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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, thereunto duly authorized.

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