Okondja is a town in Haut-Ogooué province, eastern Gabon. It is the capital of the Sebe-Brikolo Department. According to the 1993 census it had a population of 5,193 and in 2013 it had an estimated population of 10,136 . It lies along National Route 15 and is served by Okondja Airport. There are significant manganese reserves in the area.