The naval Battle of Drepana (or Drepanum) took place in 249 BCE during the First Punic War near Drepana (modern Trapani) in western Sicily, between a Carthaginian fleet under Adherbal and a Roman fleet commanded by Publius Claudius Pulcher.

Pulcher was blockading the Carthaginian stronghold of Lilybaeum (modern Marsala) when he decided to attack their fleet, which was in the harbour of the nearby city of Drepana. The Roman fleet sailed by night to carry out a surprise attack but became scattered in the dark. Adherbal was able to lead his fleet out to sea before it was trapped in harbour; having gained sea room in which to manoeuvre he then counter-attacked. The Romans were pinned against the shore, and after a day of fighting were heavily defeated by the more manoeuvrable Carthaginian ships with their better-trained crews. It was Carthage's greatest naval victory of the war; they turned to the maritime offensive after Drepana and all but swept the Romans from the sea. It was seven years before Rome again attempted to field a substantial fleet, while Carthage put most of its ships into reserve to save money and free up manpower.