Lucius Cornelius Cinna (Latin: L·CORNELIVS·L·F·L·N·CINNA), a member of the Cinna family of the Cornelii of ancient Rome, was a supporter of Marius in his contest with Sulla. After serving in the war with the Marsi as praetorian legate, he was elected consul in 87 BC.

Breaking the oath he had sworn to Sulla that he would not attempt any revolution in the state, Cinna allied himself with Marius, raised an army of Italians, and took possession of the city. Soon after his triumphant entry and the massacre of the friends of Sulla, by which he had satisfied his vengeance, Marius died. Lucius Valerius Flaccus became Cinna's colleague, and on the murder of Flaccus, Gnaeus Papirius Carbo. In 84, however, Cinna, who was still consul, was forced to advance against Sulla; but while embarking his troops to meet him in Thessaly, he was killed in a mutiny.