In Greek mythology, King Tros of Dardania (1375 BC - 1328 BC), son of Erichthonius from whom he inherited the throne and the father of three named sons: Ilus, Assaracus, and Ganymede. He is the eponym of Troy, also named Ilion for his son Ilus.

When Zeus abducted Ganymede, Tros grieved for his son. Sympathetic, Zeus sent Hermes with two horses so swift they could run over water. Hermes also assured Tros that Ganymede was immortal and would be the cupbearer for the gods, a position of much distinction.

In variant versions Ganymede is son of Laomedon son of Ilus son of Tros.

It was from Tros that the Dardanians were called Trojans and the land named the Troad.