Ōhara (大原町, Ōhara-machi) was a town located in Isumi District, Chiba Prefecture, Japan.

Ōhara was formed on March 31, 1955 by the merger of the villages of Tōkai, Azuma and Namihana.

The town's economy was largely based on commercial fishing.

The town was a sister city of Duluth, Minnesota in the United States.

This Chiba Prefecture location article is a stub.