Tsukabaru Dam (Japanese: 塚原ダム) is a concrete gravity dam built on the Mimi River for hydro-electric power generation in the Miyazaki Prefecture in Japan. The dam, built by the Kyushu Electric Power Co, Ltd. in 1938, was commissioned only in 1993. When built to a height of 87 m (285 ft) it was the highest gravity type dam in Japan, only to be surpassed later by the Kamishiba Dam raised in the uppermost reaches of the Mimi River.