was a town located in Imizu District, Toyama Prefecture, Japan.
In 2003, the town had an estimated population of 32,770 and a population density of . The total area was .
On November 1, 2005, Kosugi, along with the city of Shinminato, the towns of Daimon and à Âshima, the village of Shimo (all from Imizu District), was merged to create the city of Imizu and no longer exists as an independent municipality.