Lycomedes is the king of the island Scyrus.
When the Trojan War began, Thetis feared for her son Achilles. She knew that he would die an early death in Troy, and attempted to defy the Fates. She took him to the court of Lycomedes. She persuaded Lycomedes to take her son in, and to raise him as a girl. During Achilles' time here, he had a son with a daughter of Lycomedes, Deidameia. Their child's name was Neoptolemus.
After Achilles' death, the Greeks, on the advice of Helenus, come to Lycomedes' court to retrieve Neoptolemus. The young man eagerly goes with them.