William II of Gruyères

William II of Gruyères (fl. first half of the twelfth century) was the first count to bear the title count of Gruyères, appearing as Willelmus comes de Grueria in 1144. The eldest son of Count William I, he and his brother Radbod were co-lords of Marsens.

The brothers were among the donors who founded Humilimont Abbey near Marsens. His wife's name is unknown, and he was succeeded by his son Rudolf I.