Mertensophryne usambarae (common name: Usambara forest toad) is a species of toad in the family Bufonidae. It is endemic to the foothills of the East Usambara Mountains, northeastern Tanzania.Its natural habitats are lowland forests. It can also persist in mildly disturbed, selectively logged forests. It is threatened by habitat loss caused by agricultural encroachment, wood extraction, and human settlement.