Ouaka [wa.ka] is one of the 20 prefectures of the Central African Republic. It borders the Democratic Republic of the Congo, covers an area of 49,900 km², and has a population of 276,710 (2003 census). In 2024, official estimates suggest the population reached 459,412 inhabitants.

The prefecture is named after the Ouaka River and its capital is Bambari.

6°00′N 21°00′E / 6.000°N 21.000°E / 6.000; 21.000