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 March 2019

Commission File Number 001-33098

Mizuho Financial Group, Inc.

(Translation of registrant’s name into English)

5-5, Otemachi 1-chome

Chiyoda-ku, Tokyo 100-8176

Japan

(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  ☒    Form 40-F  ☐

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):  ☐

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):  ☐

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.    Yes  ☐    No  ☒

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):82-                    .

THIS REPORT ON FORM 6-K SHALL BE DEEMED TO BE INCORPORATED BY REFERENCE INTO THE PROSPECTUS FORMING A PART OF MIZUHO FINANCIAL GROUP, INC.’S REGISTRATION STATEMENT ON FORM F-3 (FILE NO. 333-213187) AND TO BE A PART OF SUCH PROSPECTUS FROM THE DATE ON WHICH THIS REPORT IS FURNISHED, TO THE EXTENT NOT SUPERSEDED BY DOCUMENTS OR REPORTS SUBSEQUENTLY FILED OR FURNISHED.

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.

March 6, 2019

To whom it may concern:

Recording of Losses and Revision to Earnings Estimates in Light of Structural Reform

Mizuho Financial Group, Inc. (the “Company”) hereby announces that it expects that losses arising from the Company’s efforts to promote structural reform will be recorded in its financial results for the fiscal year ending March 31, 2019.

The Company resolved at the meeting of the Board of Directors held today to revise the previously announced earnings estimates for the fiscal year ending March 31, 2019, as follows.

Please note that the estimate for annual cash dividends per share for shareholders of common stock remains unchanged.

The Company plans to announce, in May of this year, the next-term business plan commencing from the fiscal year ending March 31, 2020, which it is currently formulating, taking into consideration the fundamental structural reform announced in November 2017, and which will set forth the basic policy of the structural reform in three areas, i.e., business structure, financial structure and management foundations.

In formulating the next-term business plan, the Company expects that losses (totaling approximately 680 billion yen¹) that were not contemplated in our previously published earnings estimate will be recorded in the financial results for the fiscal year ending March 31, 2019 in respect of the Company’s principal consolidated subsidiaries in Japan, i.e., Mizuho Bank, Ltd., Mizuho Trust & Banking Co., Ltd. and Mizuho Securities Co., Ltd., for the following reasons:

Since the implementation of the in-house company system introduced in fiscal 2016, our group has been endeavoring to enhance the sophistication of its management accounting capabilities to support the in-house company system and plans to apply such enhancements in connection with the next-term business plan. Such endeavors result in some changes to management accounting which affect the application of impairment losses on fixed assets. We are also revising our future earnings plans, branch network strategy, etc., of each business area pursuant to the next-term business plan. We expect that these revisions, combined with the management accounting enhancements mentioned above, will result in impairment losses on fixed assets, including software attributable to the domestic retail business division and branches that are scheduled to be closed, which are to be recorded as Extraordinary Losses.

Amid growing uncertainty in financial markets, with an aim to achieve a more stable earnings structure as well as a solid financial base that is capable of responding to changes in the business environment, the Company will implement the restructuring of its securities portfolio in respect of past investments in foreign bonds, etc., made by the markets division. In addition, the Company plans to enhance the sophistication of its derivative valuation methods, including by more precisely reflecting the counterparty risk of the individual parties to relevant transactions in determining the fair market value of the transactions. The losses, consisting primarily of loss on sales related to securities, are expected to arise as a result of the foregoing initiatives and are to be included within Ordinary Expenses.

These figures are estimated as of today and will not be finalized until the financial results for the fiscal year ending March 31, 2019 are determined.

For the reasons stated in 1. above, the Company has revised the published consolidated earnings estimates for fiscal 2018 as follows.

After the revision to the earnings estimates, Common Equity Tier 1 capital ratio*, which is the foundation for performing a stable financial function, is still expected to be higher than the target of the current medium-term business plan, i.e., 10% as of March 31, 2019.

The Company has not revised the estimates for annual cash dividends of ¥7.50 per share and fiscal year-end cash dividends of ¥3.75 per share.

- 2 -

The outline of the next-term business plan, which is scheduled to be announced in May of this year, is as follows.

We believe that the recording of losses described in 1. above will contribute to these goals.

Under the next-term business plan, we recognize that the structural issues that we face include the need to respond to structural changes in customer needs, resolve the mismatch in the allocation of management resources, etc., that has been arising over many years of business operations, and respond to new customer needs. Based on this recognition, we are considering the reform of our business structure, financial structure and management foundations with a focus on stock business variables and to achieve qualitative changes in these areas. We will aim to create value for our stakeholders through specific business initiatives to be developed pursuant to the reforms in the future.

In the next-term business plan, we will work on “structural reforms to advance our business”, and we consider its significance as follows:

Based on our view that the business environment will continue to be challenging for the foreseeable future, we plan to implement currently feasible measures, accelerate the elimination of structural issues, reduce earnings volatility, and further solidify our stable earnings foundation.

Based on the structural changes in customer needs due to an aging society with low birthrate, digitalization, globalization, etc., we believe that the priority business domains in which we should aim for earnings growth over the medium-to-long term are as follows.

In addition, to respond to diversification of lifestyles and changes in societal structures such as the expansion of the sharing economy, we will actively reconstruct our business portfolio through open collaboration with other industries and strategic investments, and expand our customer base and solutions domains in areas where financial and non-financial businesses overlap.

Furthermore, we will promote the “transformation to a new business and working style” to adapt our HR management, IT systems, office and branch environments, etc., in a manner that is conducive to the implementation of these business strategies.

End of document

- 3 -

(Reference) Overview of the Company’s principal consolidated subsidiaries in Japan

- 4 -