In Greek mythology, Cretheus (; Kretheus) was the king and founder of Iolcus, the son of Aeolus (son of Hellen) and Enarete. His wives were Tyro and either Demodice or Biadice. With Tyro, he fathered Aeson, Pheres, and Amythaon. He also had several daughters, namely Hippolyte, future wife of Acastus (otherwise known as Astydameia); Myrina, who married Thoas; and an unnamed daughter, who became the mother of Asterius by Teutamus.