The most celebrated of Nyungwe's primates is the Ruwenzori colobus a race of the more wide spread Angola colobus which is restricted to the Albertine Rift. The Ruwenzori colobus is highly arboreal and acrobatic leaf-eater, easily distinguished from any other primate found in Nyungwe by its contrasting black over all colour and snow-white whiskers, shoulders and tail tip. Although all colobus monkeys are very sociable, the ones in Nyungwe are unique in so far as they typically move in troops of several hundred animals.
A semi-habituated troop of 400, resident in the forest around the campsite, is though to be the largest troop of arboreal primates anywhere in Africa- else where in the world, only the Chinese golden monkey moves in groups of a comparable number. Most of the other monkeys in Nyungwe are guenons, the collective name for the taxonomically confusing cercopithecus genus.
Other types of monkeys in Nyungwe National Park are the L'Hoest's monkey, Silver monkey, golden monkey, Owl faced monkey, red tailed monkey, Dent's Mona monkey, crowned monkey, Vervet monkey, and Olive baboon which is a savanna monkey that is occasionally seen along the road through Nyungwe, Grey-cheeked mangabey is an arboreal monkey of the forest interior.
In addition to the chimpanzees and monkeys, Nyungwe harbors four types of prosimian, small nocturnal primates more closely related to the lemurs of Madagascar than to any other primates of the African main land. These are three species of bush baby or galago (group of tiny, hyper active wide – eyed insectivores) and the sloth – like potto. All are very unlikely to be encountered by tourists.