Publius Cornelius Lentulus Spinther (died c. 48 bc) was a leading supporter of the Roman general Pompey the Great during the Civil War (49–45 bc) between Pompey and Julius Caesar; he was a brother of Lentulus Crus.
As curule aedile, Lentulus in 63 helped Cicero suppress Catiline’s conspiracy to overthrow the government. He was praetor in 60 and with Caesar’s aid became governor of the province of Nearer Spain in 59. As consul in 57 he worked to recall Cicero from exile and to restore his property to him. Lentulus governed Cilicia from 56 to 53. Despite his debt to Caesar, he joined the Pompeians in 49. Captured at the battle of Corfinium (Italy), he was granted clemency by Caesar, but he subsequently again went over to Pompey. After Pompey was decisively defeated at Pharsalus, Thessaly, in 48, Lentulus escaped to Rhodes; soon thereafter he fell into Caesar’s hands and was executed.