The Northwestern Congolian lowland forests (French: Forêts de plaine du nord-ouest du Congo) is a tropical moist broadleaf forest ecoregion that spans Cameroon, Gabon, the Republic of Congo, the Central African Republic and a minuscule part of the Democratic Republic of the Congo.

It forms part of the larger Congolian rainforests region in Central Africa.

[4] Characteristic tree species are Entandrophragma congoense, Pentaclethera eetveldeana, Pericopsis elata (also known as African teak), and Gilbertiodendron dewevrei.

[2] Primates richness is the highest in Africa; Cameroon alone has 29 species of primate, including the Western lowland gorilla, the vulnerable mandrill (Mandrillus sphinx), and the endangered Chimpanzee (Pan troglodytes).

[8] Protected areas include: Dzanga-Sanga, Dzanga-Ndoki, Nouabale-Ndoki, and Lobéké national parks and the Dzanga Sangha Special Reserve form the transboundary Dzanga-Sangha Complex of Protected Areas that extends across 4,589 km2 of Cameroon, Central African Republic, and Republic of the Congo.