Suboyu is a village in Tatvan District, in Bitlis Province, Türkiye. Suboyu lies at 1,608 m above sea level, in the İhtiyarşahap Dağı mountains. It has 56 inhabitants. The nearest city is Tatvan, 32 km to the northwest. Among the landmarks around are Cathedral of the Holy Cross (43 km), Holy Cross Monastery of (11.3 km) and Monastery of Surp Gevork of Goms (23 km).