Kumamoto Prefecture is a prefecture of Japan located on the island of Kyūshū. Kumamoto Prefecture has a population of 1,748,134 and has a geographic area of 7,409 square kilometres (2,861 sq mi). Kumamoto Prefecture borders Fukuoka Prefecture to the north, Ōita Prefecture to the northeast, Miyazaki Prefecture to the southeast, and Kagoshima Prefecture to the south.

Kyūshū is the third-largest island of Japan's four main islands and the most southerly of the four largest islands. In the past, it has been known as Kyūkoku , Chinzei and Tsukushi-no-shima . The historical regional name Saikaidō referred to Kyushu and its surrounding islands. Kyushu has a land area of 36,782 square kilometres (14,202 sq mi) and a population of 14,311,224 in 2018.