In Greek mythology, Lelex (/ˈliːlɪks/; Ancient Greek: Λέλεξ, gen. Λέλεγος) was one of the original inhabitants of Laconia which was called after him, its first king, Lelegia.

Lelex was said to be autochthonous^[1] or his father was the sun-god Helios or the sea-god Poseidon.^[2] He was married to the Naiad nymph Cleocharia and became the father of several sons, including Eurotas,^[3] and possibly Myles and Polycaon.^[4] Some called his wife Peridia and their children were Myles, Polyclon, Bomolochus and Therapne.^[5]

In one tradition, again, Lelex was described as the son of Spartus, and father of Amyclas.^[6] The eponymous heroine Lakonia was credited to be a daughter of Lelex as well.^[2]

Through Myles, Lelex was the grandfather of Eurotas, who had a daughter named Sparta.^[7] This woman later marry Lacedaemon^[8] who named the city of Sparta after his wife; however, the city's name would also be his own, as it was called either Lacedaemon or Sparta interchangeably.

Sources indicate that Perseus was a descendant of Lelex. The latter's great-granddaughter Sparta gave birth to a daughter named Eurydice who had married Acrisius, the king of Argos. Eurydice became the mother of Danaë, thus making her Perseus’ grandmother.^[9]

Lelex appears to have been conceived by ancient mythographers as the eponymous founder of the Leleges, a semi-mythical people who lived on both sides of the Aegean Sea.^[10] He had a heroön at Sparta.^[11]