In Greek mythology, Oeneus, or Oineus was a Calydonian king, son of Porthaon, husband of Althaea and father of Meleager and Melanippe. He introduced winemaking to Aetolia, which he learned from Dionysus. His brother's, Agrius', sons deposed him but Diomedes put Oeneus back on the Calydonian throne. He was buried in Argos by Diomedes. He sent Meleager out to find heroes to kill the Calydonian Boar, which was ravaging Calydon because Oeneus had forgotten to honor Artemis at the harvest ceremonies.

Oeneus was the father of Tydeus by Periboea, though Tydeus was exiled from Aetolia and appears in myths concerning Argos.