Gorgonopsia is an iconic group of saber-toothed, carnivorous therapsids. They have a rich fossil record in the Karoo Basin of South Africa, but are also relatively common components of coeval Malawian, Tanzanian, Zambian, and Russian assemblages. Phylogenetic analyses have demonstrated that African gorgonopsians form a monophyletic subclade distinct from their Russian relatives, which all fall out near the root of the cladogram, thus suggesting a northern hemisphere origin for the clade as a whole. Surprisingly, recent research has demonstrated that a species of Inostrancevia, a genus previously recorded solely in Russia, occurs in the upper Daptocephalus Assemblage Zone of the Karoo Basin, perhaps the result of immigration following the demise of endemic rubidgeine gorgonopsians in the lower subzone of that unit. Here we describe a large, isolated gorgonopsian premaxilla from a bone-rich, conglomeratic interval at the base of the Usili Formation of Tanzania's Ruhuhu Basin. Based on its stratigraphic position and fossil content, this unit likely correlates with the Cistecephalus Assemblage Zone. The premaxilla can be confidently referred to the genus Inostrancevia on the basis of its four incisors, a feature unique to Inostrancevia among gorgonopsians. In contrast to the disjunct distribution of inostranceviines and rubidgeines in the uppermost Permian of South Africa, the Tanzanian Inostrancevia likely overlapped with large-bodied rubidgeines such as Dinogorgon and Rubidgea.