Carnea (Greek: Κάρνεια, Karneia, or Κάρνεα, Karnea) was the name of one of the great national festivals of Sparta, held in honour of Apollo Carneus. Whether Carneus (or Carnus) was originally an old Peloponnesian divinity subsequently identified with Apollo, or merely an "emanation" from him, is uncertain; but there seems no reason to doubt that Carneus means "the god of flocks and herds" (Hesychius, s.v. Κάρνος), in a wider sense, of the harvest and the vintage. The chief centre of his worship was Sparta, where the Carnea took place every year from the 7th to the 15th of the month Carneus (=Metageitnion, August). During this period all military operations were suspended.

The Carnea appears to have been at once agrarian, military and piacular in character. In the last aspect it is supposed to commemorate the death of Carnus, an Acarnanian seer and favourite of Apollo, who, being suspected of espionage, was slain by one of the Heraclidae during the passage of the Dorians from Naupactus to Peloponnesus. By way of punishment, Apollo visited the army with a pestilence, which only ceased after the institution of the Carnea. The tradition is probably intended to explain the sacrifice of an animal (perhaps a later substitute for a human being) as the representative of the god. The agrarian and military sides of the festival are clearly distinguished.