The Zanj sun squirrel (Heliosciurus undulatus) is a species of rodent in the family Sciuridae found in eastern Africa.

There is geographical variation throughout its range with the animals found inland at higher elevations being the darkest and richest in colour while those from the north of its range are paler while the southerly populations are duller and greyer.

[1] Little is known about the biology of the Zanj sun squirrel but it is omnivorous eating fruits, leaves, seeds, buds and palm dates.

[2] The coastal forests inhabited by Zanj sun squirrels are under threat from clearance for expanding agriculture, charcoal burning and fuel wood extraction, uncontrolled fires, unsustainable logging, human settlement, and destructive mining practices.

It is unknown how these factors have affected this species so the IUCN give the status as Data Deficient.