is a town located in Kayabe District, Oshima, Hokkaidō, Japan.On April 1, 2005, the neighboring town of Sawara merged into Mori. As of this merger, but with March 31, 2008 population data, the town has an estimated population of 18,693 and a density of 53.5 persons per km². The (post-merger) total area is 3,168.27 km².