Marcus Petronius Sura Mamertinus (died between 190 and 192 AD) was a Roman consul who lived in the 2nd century and was one of the sons-in-law of the Emperor Marcus Aurelius.
Mamertinus came from a wealthy, well-connected family of African origin—possibly from Egypt. His father, Marcus Petronius Mamertinus, was suffect consul in 150 and his mother's name is unknown. He had a brother, Marcus Petronius Sura Septimianus, who served as consul in 190, and a sister whose husband was the illustrious senator Marcus Antoninus Antius Lupus. Mamertinus was a kinsman of the grammarian Marcus Cornelius Fronto.
During the reign of Marcus Aurelius (161-180) and Faustina the Younger (161-175), Mamertinus married their daughter Annia Cornificia Faustina Minor in Rome.
Sometime after 173, Cornificia Faustina bore Mamertinus a son, Petronius Antoninus.
Mamertinus and his family could have been at the winter camp of Marcus Aurelius in early 180. When Marcus Aurelius died later that year, Mamertinus' brother-in-law Commodus succeeded him as Emperor. In 182, Mamertinus served as consul. Sometime between 190 and 192, Commodus ordered the deaths of Mamertinus, his son, his brother and his sister's family. Cornificia Faustina survived the political persecutions of her brother and later remarried.