Crook County is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 24,738. The county seat is Prineville. The county is named after George Crook, a U.S. Army officer who served in the American Civil War and various Indian Wars.

Prineville is a city in and the seat of Crook County, Oregon, United States. It was named for the first merchant to establish businesses in the present location, Barney Prine. The population was 10,429 at the 2020 census.