Kunisaki (国東市) is a city located in Ōita Prefecture, Kyushu, Japan.
The modern city of Kunisaki was founded on March 31, 2006, from the merger of the former town of Kunisaki, absorbing the towns of Aki, Kunimi and Musashi (all from Higashikunisaki District).
As of March 31, 2017, the city has an estimated population of 29,098, with 13,223 households and a population density of 92 /km2. The total area is 317.84 km2.
Oita Airport is located in Kunisaki.