The sub-prefectures of the department are Bouko, Bouna, Ondéfidouo, and Youndouo.
[3] Using current boundaries as a reference, from 1974 to 2005 the department occupied the territory of Bounkani Region.
[3] In 2011, districts were introduced as new first-level subdivisions of Ivory Coast.
At this time, Bouna Department became part of Bounkani Region in Zanzan District.
The fourth portion consists of a large section of Comoé National Park that was removed from any department.