Kōyama (高山町 Kōyama-chō) was a town located in Kimotsuki District, Kagoshima, Japan.
On July 1, 2005 Kōyama was merged with the town of Uchinoura, also from Kimotsuki District, to form the new town of Kimotsuki.
In 2003, the town had an estimated population of 14,441 and a density of 112.15 persons per km². The total area was 128.76 km².