The Ugandan red colobus (Piliocolobus tephrosceles) or ashy red colobus is an endangered species of red colobus monkey, recognised as a distinct species since 2001. There is disagreement however over taxonomy with many considering the Ugandan red colobus to be a subspecies (Procolobus rufomitratus tephrosceles). The Ugandan red colobus is an Old World monkey which is found in 5 different locations across Uganda and Tanzania.

Recognised as a distinct species in 2001 the Ugandan red colobus had previously been considered a subspecies of P. badius, and later a subspecies of P. foai. There is currently a debate as to whether it should be considered a subspecies of P. rufomitratus.

The Ugandan red colobus has a rust-red cap with a dark grey to black face, although infants are born with completely black faces. There is more variation amongst the coat colours of the Ugandan red colobus with back colour ranging from black to dark grey through to a reddish brown. The sides of the body and the arms and legs are a light grey. They have very long dark to light brown tails which they rely on for balancing when climbing and leaping through the canopy. The Ugandan red colobus has dark grey to black hands and feet and their feet are very long which helps them leap large distances.

The Ugandan red colobus, like all colobus monkeys, has thumbs which are so reduced in size they are almost absent. It is thought this feature may help in brachiation when moving through the canopy.

There is strong sexual dimorphism; the males are much larger than the females. The average male weighs around 10.5 kg and the females weigh around 7 kg.

The Ugandan red colobus is found only in Africa. It has a distribution spanning 1000 km of East Africa but populations are only found in 5 separate forested areas. These areas are in west Tanzania at the edge of Lake Victoria, in Gombe and Mahale Mountains at the edge of Lake Tanganyika, on the Ufipa Plateau and in west Uganda in Kibale National Park. The Ugandan population is the largest and it has been suggested that this is the only viable population with around 17,000 individuals. It is possible, though yet to be verified, that the Ugandan red colobus might also be located in Rwanda, Burundi and the eastern Democratic Republic of the Congo.

The habitat of the Ugandan red colobus varies by population. Kibale National Park, Uganda, inhabited by the largest population, is a moist evergreen tropical forest. Kibale National Park has been a protected area since 1993. Before 1993 parts of the forest were subject to logging of different degrees of severity. The habitat of the Ugandan red colobus in the Mbisi Forest Reserve on the Ufipa Plateau is fragmented and severely degraded. Unlike Kibale where significant expanses of undisturbed forest remain.