Sawauchi (沢内村 Sawauchi-mura) was a village located in Waga District, Iwate, Japan.
On November 1, 2005 Sawauchi was merged with the town of Yuda to form the new town of Nishiwaga and no longer exists as an independent municipality.
As of 2003, the village had an estimated population of 3,765 and a density of 13.15 persons per km². The total area was 286.22 km².