Parnaíba (Parnahyba) was a Brazilian cargo ship sunk during World War II by the German submarine U-162 on May 1, 1942, while sailing east of Trinidad and Tobago in the Atlantic Ocean, carrying coffee, cocoa, castor bean oil, cotton, and other commodities.

Made with a steel hull, she had 6,692 gross register tonnage, and was propelled by steam turbines coupled to a quadruple expansion engine, allowing her to reach a speed of 12 knots (22 km/h; 14 mph).

She was renamed Parnaíba (Parnahyba) and registered in Rio de Janeiro under number 17, being operated, from 1923, by Lloyd Brasileiro, which acquired full ownership of her in 1927.

[3] On May 1, 1942, after almost two months without attacks on Brazilian ships (since the sinking of the Cairu on March 8), the Parnaíba, commanded by Captain Raul Francisco Diégoli, was east of the island of Trinidad and Tobago and north of the Guianas (coordinates: 10° 12' N 57° 16' W), loaded with 40,950 bags of coffee, 30,000 of cocoa, 27,155 of bran, 25,000 bales of leather, 17,585 of castor beans, and 15,108 of miscellaneous cargo, totaling 155,739 volumes.

[4] Shortly before 3 p.m. (8:46 p.m. Central European Time), the German submarine U-162, commanded by Captain Jürgen Wattenberg, fired its first torpedo at the ship, hitting her at midship.

In the meantime, while a distress call was being issued by Captain Diégoli who was still on board, a second torpedo hit the ship, and soon afterward the Germans fired several cannon shots at Parnahyba.