Achaeus of Eretria (Ancient Greek: Ἀχαιός; born 484 BC in Euboea) was a Greek playwright author of tragedies and satyr plays, variously said to have written 24, 30, or 44 plays, of which 19 titles are known: Adrastus, Aethon, Alcmeon, Alphesiboea, Athla, Azanes, Cycnus, Eumenides, Hephaestus, Iris, Linus, Moirai (Fates), Momus, Oedipus, Omphale, Philoctetes, Phrixus, Pirithous, and Theseus.