Kouilou is one of the ten regional administrative divisions of the Republic of the Congo. Covering the country's coastline, it is home to about 592,100 people. The region borders Niari region, and internationally, Gabon and the Cabinda area of Angola. The regional capital is Pointe-Noire.
Kouilou is also the name of a river, the Kouilou-Niari River.
