Mosar is a village in Ushachy Raion, in Vitebsk Region, Belarus. Mosar lies at 144 m above sea level. It has 173 inhabitants. The nearest city is Polotsk, 42 km to the north. Among the landmarks around are Saint Lawrence church in Ušačy (15.2 km), Church of Saint Anthony of Padua in Hubin (11.4 km) and Krasny Castle (17.3 km).
Also written Мосар.