Apis (Ancient Greek: Ἆπις) was a king of Argos in Greek mythology. He was a son of Phoroneus by the nymph Teledice, and brother of Niobe. During his reign he established a tyrannical government and called the Peloponnesus after his own name Apia, but was eventually killed in a conspiracy headed by Thelxion, king of Sparta, and Telchis. In the former of these passages Apollodorus of Athens states that Apis, the son of Phoroneus, was killed by Aetolus; but this is a mistake arising from the confusion of this Apis with another Apis who was the son of Jason, who was killed by Aetolus during the funeral games celebrated in honor of Azanes. Argus Panoptes, a descendant of his sister Niobe, avenged his murder by putting Thelxion and Telchis to death.
Apis, the son of Phoroneus, is said, after his death, to have been worshipped as a god under the name of Serapis (Σάραπις). This confusion is still more manifest in the tradition, that Apis gave his kingdom of Argos to his brother, and went to Egypt, where he reigned for several years afterwards. Apis is spoken of as one of the earliest lawgivers among the Greeks. Both these stories show that Egyptian myths were mixed up with the story of Apis, see Apis (Egyptian mythology).