FBR Fibria Celulose S.A.

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 of

the Securities Exchange Act of 1934

Dated March 3, 2017

Commission File Number: 1-15018

Fibria Celulose S.A.

Fidêncio Ramos, 302 — 3rd and (part of) 4th floors

Edifício Vila Olímpia, Torre B, Bairro Vila Olímpia

04551-010, São Paulo, SP, Brazil

(Address of principal executive offices)

(Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or 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, the Registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.)

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

FIBRIA CELULOSE S.A.

Publicly-Held Company

CNPJ/MF No. 60.643.228/0001-21

NIRE 35.300.022.807

NOTICE TO THE MARKET

FIBRIA CELULOSE S.A. (“ Fibria ”) (BM&FBOVESPA: FIBR3 | NYSE: FBR) hereby informs its shareholders and the market in general that as approved by its Board of Directors in the meeting held on November 30, 2016, the execution, on February 27 th , 2017, of an affreightment agreement of 5 vessels (Consecutive Voyage Contract - CVC) with Pan Ocean Co. Ltd., a South Korean company, at a total estimated amount of approximately USD 636 million, diluted over the period the service is provided.

The Contract will come into force on the date of its execution with provision for its termination in 2035, and may be extended for a period of 5 or 10 years at Fibria’s sole discretion.

Fibria underlines, accordingly, by means of the release of the information in this Notice to the Market, its commitment to transparency with its shareholders and investors.

São Paulo, March 3rd, 2017.

FIBRIA CELULOSE S.A.

Guilherme Perboyre Cavalcanti

Chief Financial and Investor Relations Officer

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