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):

Yes ______ No ___X___

Indicate by check mark whether 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:

Yes ______ No ___X___

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

GAFISA S.A.

Corporate Taxpayer’s ID (CNPJ/MF):° 01.545.826/0001-07

Company Registry (NIRE): 35.300.147.952

Publicly-Held Company

NOTICE TO THE MARKET

GAFISA S.A. (BOVESPA: GFSA3) (“Gafisa” or “Company”) hereby announces that it sextended the maturity of Company's debt totaling four hundred fifty-six million, three hundred sixteen thousand, eight hundred and thirty-two reais and eighty-three centavos (R$456,316,832.83). The Company's debts will now mature in 2020 and 2021. The debt extension, carried out under the condition precedent of a minimum capital increase of two hundred million reais (R$200,000,000.00), complies with one of the conditions of the obligation of Wishbone Management, LP, a Company shareholder, in partnership with Conifer Capital Management, LLC and investment funds managed by its affiliated companies. Said condition refers to subscribing to shares and eventual unsubscribed shares within the context of the capital increase to be submitted to approval by the extraordinary shareholders’ meeting called to convene on second call at 10:00 a.m., on December 20, 2017.

São Paulo, December 19, 2017.

GAFISA S.A.
Carlos Calheiros
Chief Financial and Investor Relations Officer