Sakamoto Dam is a dam in the Gunma Prefecture of Japan. It forms Lake Usui.

Sakamoto Dam
LocationGunma Prefecture, Japan.
Coordinates36°21′12″N 138°42′27.3″E / 36.35333°N 138.707583°E / 36.35333; 138.707583
Construction began1985
Opening date1994; 30 years ago (1994)
Dam and spillways
Type of damGravity
ImpoundsUsui River
Height36.3 m (119 ft)
Length85 m (279 ft)
Reservoir
CreatesLake Usui
Total capacity778,000 m3 (27,500,000 cu ft)
Catchment area13.7 km2 (5.3 sq mi)
Surface area7 hectares (17 acres)
Lake Usui