Ngounié is a province of south-central Gabon covering an area of 3,775 kilometres (2,346 mi). Its capital is Mouila. At the 2013 census it had 100,838 inhabitants. In 2016, its governor was Benjamin Nzigou.
The province is named after the Ngounié River, which crosses it with its many tributaries.
In December 1858 the French explorer Paul Du Chaillu navigated the Nguoiné river upstream to Fougamou. On his journey, he met several local tribes whom he described in his diaries of his second voyage. Later, Catholic missions were built in Mandji, Sindara, and Saint Martin, whose architecture attracts many tourists.