In Greek mythology, Oebalus, also spelled Oibalus or Oibalius (Ancient Greek: Οἴβαλος, Oíbalos), was a king of Sparta.

Oibalus was the son of either Cynortas or Argalus. He was the second husband of Princess Gorgophone and thus son-in-law of the hero Perseus. With her or by the Naiad Bateia, Oibalos fathered Tyndareus, Icarius and Hippocoon, as well as a daughter, Arene, who married her half-brother Aphareus. The nymph Pirene and Hyacinth were also called the daughter and son of Oebalius respectively. His grandchildren, the Dioscuri, were usually referred to as Oibalids or Oebalidae.

Oebalus was often confused with Gorgophone's first husband, Perieres, son of Aeolus. They were separate people, usually unrelated, though Oebalus was sometimes said to be Perieres's son.

Wikipedia gives a comparative table of Oebalus's family, setting his attested relationships side by side across the ancient authors Hesiod, Apollodorus, Dictys, Hyginus, Pausanias, and Lucian. The table is organized by relation — his parentage, his consort, and his children — and marks which classical source records each link.

For his parentage, the sources name either Cynortas or Argalus as his father. For his consort, Gorgophone is given, with the Naiad Bateia named in her place by some authors. Among the children attributed to him are Tyndareus, Icarius, Hippocoon, the daughter Arene, the nymph Pirene, and Hyacinth, with the various authors agreeing on different combinations of these offspring.

In the Spartan king lists Oebalus stands within the royal succession of Sparta: he is given as preceded by Cynortas and succeeded by his son Tyndareus, who held the kingship in his first reign.