Report of Foreign Issuer (6-k)

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

For the month of February, 2018

Commission File Number 1-15106

PETRÓLEO BRASILEIRO S.A.—PETROBRAS

(Exact name of registrant as specified in its charter)

Brazilian Petroleum Corporation—PETROBRAS

(Translation of Registrant’s name into English)

Avenida República do Chile, 65

20031-912 - Rio de Janeiro, RJ

Federative Republic of Brazil

(Address of principal executive office)

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

Form 20-F ☒ Form 40-F ☐

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 ☒

LOGO

PETROBRAS ANNOUNCES REDEMPTION PRICES

FOR THREE SERIES OF NOTES

RIO DE JANEIRO, BRAZIL – February 22, 2018 – Petróleo Brasileiro S.A. – Petrobras (“ Petrobras ”) (NYSE: PBR) announces that its wholly-owned subsidiary Petrobras Global Finance B.V. (“ PGF ”) has delivered notices to holders in connection with its redemption of the outstanding 3.000% Global Notes due 2019 (“ 3.000% Notes ”), 3.25% Global Notes due 2019 (“ 3.25% Notes ”) and 7.875% Global Notes due 2019 (“ 7.875% Notes ” and, together with the 3.000% Notes and the 3.25% Notes, the “ Notes ”) announcing the redemption prices for the Notes. The redemption date for the Notes will be February 26, 2018 (“ Redemption Date ”).

Title of Security

CUSIP

ISIN

Common
Code

Aggregate
Principal Amount
to be Redeemed

Make-
Whole
Premium ⁽¹⁾

Interest ⁽¹⁾

Redemption
Price ⁽¹⁾

3.000% Global Notes due 2019

71647N AB5

US71647NAB55

N/A

US$691,833,000

US$5.28

US$3.42 ⁽²⁾

US$1,008.70

3.25% Global Notes due 2019

N/A

XS0835886598

083588659

€668,247,000

€39.57

€29.47 ⁽³⁾

€1,069.04

7.875% Global Notes due 2019

71645WAN1

US71645WAN11

041298995

US$558,351,000

US$54.39

US$35.22 ⁽⁴⁾

US$1,089.61

⁽¹⁾	Per US$1,000 or €1,000, as applicable. Figures have been rounded for ease of presentation.

⁽²⁾	Accrued interest on the principal amount from January 15, 2018 to (but not including) the Redemption Date.

⁽³⁾	Accrued interest on the principal amount from April 1, 2017 to (but not including) the Redemption Date.

⁽⁴⁾	Accrued interest on the principal amount from September 15, 2017 to (but not including) the Redemption Date.

Payment on the 3.000% Notes and the 7.875% Notes will be made prior to 3:00 pm New York time on the business day preceding the Redemption Date by credit to the account of The Bank of New York Mellon (the “ Trustee ”), the trustee and paying agent for the 3.000% Notes and the 7.875% Notes. Payment on the 3.25% Notes will be made prior to 12:00 pm London time on the business day preceding the Redemption Date by credit to the account of The Bank of New York Mellon, London Branch, as principal paying agent for the 3.25% Notes (the “ Principal Paying Agent ”).

www.petrobras.com.br/ir

Contacts:

PETRÓLEO BRASILEIRO S.A. – PETROBRAS | Investor Relations Department | e-mail: petroinvest@petrobras.com.br

Av. República do Chile, 65 – 10th floor, 1002 – B – 20031-912 – Rio de Janeiro, RJ | Phone: 55 (21) 3224-1510 / 3224-9947

FORWARD-LOOKING STATEMENTS

This release includes forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, that are subject to risks and uncertainties. The forward-looking statements, which address the Company’s expected business and financial performance, among other matters, contain words such as “believe,” “expect,” “estimate,” “anticipate,” “optimistic,” “intend,” “plan,” “aim,” “will,” “may,” “should,” “could,” “would,” “likely,” and similar expressions. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date on which they are made. There is no assurance that the expected events, trends or results will actually occur. We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information or future events or for any other reason.

The Company’s actual results could differ materially from those expressed or forecast in any forward-looking statements as a result of a variety of assumptions and factors. These factors include, but are not limited to, the following: (i) failure to comply with laws or regulations, including fraudulent activity, corruption, and bribery; (ii) the outcome of ongoing corruption investigations and any new facts or information that may arise in relation to the “Lava Jato Operation”; (iii) the effectiveness of the Company’s risk management policies and procedures, including operational risk; and (iv) litigation, such as class actions or proceedings brought by governmental and regulatory agencies. A description of other factors can be found in the Company’s Annual Report on Form 20-F for the year ended December 31, 2016, and the Company’s other filings with the U.S. Securities and Exchange Commission.

LOGO

For the 3.000% Notes, the Trustee will cause funds to be paid to The Depository Trust Company for further payment to its participants in the aggregate amount of US$697,849,737.28 (or approximately US$1,008.70 per US$1,000 principal amount of the 3.000% Notes), which constitutes the redemption price of the 3.000% Notes. The redemption price includes accrued and unpaid interest on the principal amount of the 3.000% Notes from January 15, 2018 to (but not including) the Redemption Date in the amount of US$2,363,762.75 (or approximately US$3.42 per US$1,000 principal amount of the 3.000% Notes) and a make-whole premium of US$3,652,974.53 (or approximately US$5.28 per US$1,000 principal amount of the 3.000% Notes).

For the 3.25% Notes, the Principal Paying Agent, as common depositary for Clearstream and Euroclear, will cause funds to be paid to its participants in the aggregate amount of €714,385,848.64 (or approximately €1069.04 per €$1,000 principal amount of the 3.25% Notes), which constitutes the redemption price for the 3.25% Notes. The redemption price includes accrued and unpaid interest on the principal amount of the 3.25% Notes from April 1, 2017 to (but not including) the Redemption Date in the amount of €19,694,978.36 (or approximately €29.47 per €$1,000 principal amount of the 3.25% Notes) and a make-whole premium of €26,443,870.28 (or approximately €39.57 per €$1,000 principal amount of the 3.25% Notes).

For the 7.875% Notes, the Trustee will cause funds to be paid to The Depository Trust Company for further payment to its participants in the aggregate amount of US$608,385,369.74 (or approximately US$1,089.61 per US$1,000 principal amount of the 7.875% Notes), which constitutes the redemption price of the 7.875% Notes. The redemption price includes accrued and unpaid interest on the principal amount of the 7.875% Notes from September 15, 2017 to (but not including) the Redemption Date in the amount of US$19,664,424.28 (or approximately US$35.22 per US$1,000 principal amount of the 7.875% Notes) and a make-whole premium of US$30,369,945.46 (or approximately US$54.39 per US$1,000 principal amount of the 7.875% Notes).

On the Redemption Date, the redemption prices, including accrued and unpaid interest, will become due and payable. Interest on the Notes will cease to accrue on and after the Redemption Date. Upon the redemption, the 3.000% Notes and the 7.875% Notes will cease to be listed on the New York Stock Exchange, the 3.25% Notes will cease to be listed on the Luxembourg Stock Exchange, and the Notes and the related guarantees by Petrobras will be cancelled and any obligation thereunder extinguished.

Because the 3.000% Notes and the 7.875% Notes are held in book-entry form, payment of the redemption prices will be made directly to the registered holders.

www.petrobras.com.br/ir

Contacts:

PETRÓLEO BRASILEIRO S.A. – PETROBRAS | Investor Relations Department | e-mail: petroinvest@petrobras.com.br

Av. República do Chile, 65 – 10th floor, 1002 – B – 20031-912 – Rio de Janeiro, RJ | Phone: 55 (21) 3224-1510 / 3224-9947

FORWARD-LOOKING STATEMENTS

LOGO

PGF intends to fund the amounts necessary to redeem the Notes with the proceeds of its previously announced notes offering completed on February 1, 2018.

For more information, please contact PGF by contacting the Investor Relations Department (telephone: +55 (21) 3224-1510/3224-9947; fax: +55 (21) 3224-6055; e-mail: petroinvest@petrobras.com.br) if you have any questions regarding this notice.

Forward-Looking Statements

This press release may contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended that are not based on historical facts and are not assurances of future results. No assurance can be given that the transactions described herein will be consummated or as to the ultimate terms of any such transactions. All forward-looking statements are expressly qualified in their entirety by this cautionary statement, and you should not place reliance on any forward-looking statement contained in this press release. Petrobras undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information or future events or for any other reason.

www.petrobras.com.br/ir

Contacts:

PETRÓLEO BRASILEIRO S.A. – PETROBRAS | Investor Relations Department | e-mail: petroinvest@petrobras.com.br

Av. República do Chile, 65 – 10th floor, 1002 – B – 20031-912 – Rio de Janeiro, RJ | Phone: 55 (21) 3224-1510 / 3224-9947

FORWARD-LOOKING STATEMENTS

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.

Date: February 22, 2018.