Masuma Dam is a gravity dam located in Chiba Prefecture in Japan.

The catchment area of the dam is 2.2 km2.

The dam impounds about 54 ha of land when full and can store 520 thousand cubic meters of water.

The construction of the dam was started on 1966 and completed in 1969.

This article about a dam or floodgate in Kantō region of Honshu, Japan is a stub.