Diagnoses and illustrations of the holotypes and paratypes are given for two new genera and seven new species of the mammalian orders Rodentia and Lagomorpha from the Upper Miocene Wood Mountain Formation of southern Saskatchewan. Taxa named include the eomyid Adjidaumo russelli, sp. nov.; the heteromyids Perognathus saskatchewanensis, perognathoides kleinfelderi, and Peridiomys borealis, spp. nov.; the entoptychine geomyid Lignimus montis, gen. et sp. nov.; and the ochotonids Hesperolagomys fluviatilis, sp. nov., and Russellagus vonhofi, gen. et sp. nov. All taxa treated in this paper are from the Kleinfelder Farm locality, near Rockglen, Saskatchewan. More detailed descriptions and comparisons will be given in a subsequent publication.