Lucius Fabius Cilo, full name Lucius Fabius Cilo Septiminus Catinius Acilianus Lepidus Fulcinianus, was a Roman senator, who was a confidant of Septimius Severus. He held a number of appointments that have been dated to the reigns of Commodus and Severus. He was twice Roman consul: the first time in 193 as a suffect, and the second time as ordinary consul in 204 with Marcus Annius Flavius Libo as his colleague. Cilo is known from numerous inscriptions and appears in the Historia Augusta and the history of Dio Cassius. He married Cilonia Fabia.