Ōita Prefecture is a prefecture of Japan located on the island of Kyūshū. Ōita Prefecture has a population of 1,136,245 and has a geographic area of 6,340 km2. Ōita Prefecture borders Fukuoka Prefecture to the northwest, Kumamoto Prefecture to the southwest, and Miyazaki Prefecture to the south.

Ōita is the capital city of Ōita Prefecture, located on the island of Kyushu, Japan. As of 30 November 2023, the city had an estimated population of 474,804 in 230867 households, and a population density of 950 persons per km2. The total area of the city is 502.38 km2 (193.97 sq mi).