Üçoyuk is a village in Pervari District, in Siirt Province, Türkiye. Üçoyuk lies at 783 m above sea level, in the Yazlıca Dağı mountains. It has 154 inhabitants. The nearest city is Siirt, 37 km to the west. Among the landmarks around are Çetin Dam (1.8 km) and Tomb of İsmail Fakirullah (31 km).