Rumoi Subprefecture is a subprefecture of Hokkaido Prefecture, Japan. As of 2011, it had a population of 52,627 and an area of 4,019.97 square kilometres (1,552.12 sq mi). The population density of the subprefecture, 13 people per km2, is very low compared to the rest of Japan. The population of Rumoi Subprefecture represents 0.96% of the overall population of Hokkaido.

Toyotomi is a town located in Sōya Subprefecture, Hokkaido, Japan. It contains the Sarobetsu Plain, which is part of Rishiri-Rebun-Sarobetsu National Park, and is famous for its hot springs.