Small mammals were sampled in Ruaha National Park in 2011. Forty-three species of small mammals (three species of Soricomorpha, 23 species of Chiroptera, 17 species of Rodentia) were documented. An additional three species of bat were documented from specimens found independently of this survey. Identifications and natural history data are presented for each of the species encountered. Particular attention was paid to the Isunkaviola Plateau, a forest habitat at higher altitudes within the Park, which had no previous study of small mammals. The fauna of Isunkaviola Plateau bears little resemblance to that of the Eastern Arc Mountains or the Southern Highlands.