The western lowland gorilla (Gorilla gorilla gorilla) is one of two Critically Endangered subspecies of the western gorilla (Gorilla gorilla) that lives in montane, primary and secondary forest and lowland swampland in central Africa in Angola, Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Equatorial Guinea and Gabon. It is the nominate subspecies of the western gorilla, and the smallest of the four gorilla subspecies.

The western lowland gorilla is the only subspecies kept in zoos with the exception of Amahoro, a female eastern lowland gorilla at Antwerp Zoo, and a few mountain gorillas kept captive in the Democratic Republic of the Congo.

Western lowland gorillas primarily live in rainforest, swamp forest, brush, secondary vegetation, clearing and forest edges, abandoned farming fields and riverine forest. They live in primary and secondary lowland tropical forest at elevations that extend from sea level up to 1,300 m (4,300 ft). The average amount of rainfall in the areas where western lowland gorillas typically reside is about 1,500 mm (59 in) a year with the greatest rainfall between the months of August and November. Western lowland gorillas are not typically observed in areas that are close to human settlements and villages. They have been known to avoid areas with roads and farms that show signs of human activity. These gorillas favor areas where edible plants are more copious. Swamp forest is now considered an important food source and habitat for the western lowland gorilla. These areas support the gorillas in both the wet and the dry season of the forest. The forest of the Republic of Congo is currently considered to host the majority of the western lowland gorilla population. They protect the gorillas with the isolation of their large swampy forest areas.

The group in this gallery of the Bai Hoku in Dzangha Ndoki National Park Central African Republic