Ilus (/ˈiːloʊs/; Greek: Ἶλος) is the name of several mythological persons associated directly or indirectly with Troy.
Homer's Iliad mentions at several points the tomb of Ilus son of Dardanus in the middle of the Trojan plain. Later writers explain him as the son and heir of Dardanus who died childless whence his brother Erichthonius gained the kingship.
Ilus (Ilos in Greek) is in Greek mythology the founder of the city called Ilios or Ilion (Latinized as Ilium) to which he gave his name. When the latter became the chief city of the Trojan people it was also often called Troy, the name by which it is best known today.
Ilus was son and heir to Tros of Dardania and brother of Assaracus and Ganymede. He won the wrestling prize at games held by the King of Phrygia and received fifty youths and maidens as his reward. The king also, on the advice of an oracle, gave him a cow and asked him to found a city where it should lie down. Ilus did so.
Ilus then prayed to Zeus for a sign and at once saw the Palladium fallen from heaven and lying before his tent but was immediately blinded for the impiety of looking on the image. He regained his sight after making offerings to Athena.
Ilus preferred his new city of Ilium to Dardania and on his father's death he remained there, bestowing the rule of Dardania on his brother Assaracus instead and so the Trojans were split into two kingdoms.