 Choctaw County is in southeastern Oklahoma, in a 10-county area designated for tourism purposes by the Oklahoma Department of Tourism and Recreation as Choctaw Country.According to the U.S. Census Bureau, the county has a total area of , of which is land and (3.7%) is water.The major streams in the county are the Kiamichi River, the Muddy Boggy River and the Clear Boggy River, which all drain into the Red River.