Montederramo is a municipality in the province of Ourense, within the autonomous community of Galicia in northwestern Spain. It belongs to the comarca (district) of Terra de Caldelas.
The municipality is located in the eastern part of Ourense province, in Galicia's mountainous interior. Like much of the surrounding region, it is characterized by a rural landscape and a small, dispersed population.
Montederramo is best known for the Monastery of Santa María de Montederramo, a former Cistercian abbey that is the area's principal historical landmark. The municipality's name is closely associated with this monastic foundation, which shaped the locality's history and remains its most notable feature.