The Guereza is distributed in Equatorial Africa where it is found in a variety of forest habitats: deciduous, evergreen, riverine, secondary, etc., and mainly close to rivers and lakes. See the distribution map at IUCN.

It belongs to the Colobini tribe of Old World Monkeys otherwise known as leaf-eating monkeys although their diet is not restricted to leaves but includes fruit, bark, seeds, etc..

It is active during the day but will spend long periods sleeping when it is not eating. It is also mainly arboreal and rarely descends to the ground.