Zeus was the father of Apollo in Greek mythology. He was the king of the gods and the god of the sky, lightning, thunder, law, order, and justice. Zeus was married to Hera, the goddess of marriage and childbirth. He was also the father of many other gods and goddesses, including Athena, Hermes, and Dionysus. Zeus and Apollo had a close relationship, with Zeus often offering guidance and protection to his son.