Cerradomys is a genus of oryzomyine rodents from eastern Bolivia, Paraguay, and central Brazil found in cerrado, Caatinga and Gran Chaco habitats. The species in this genus have historically been placed in Oryzomys, but according to cladistic research, they are not more closely related to the type species of Oryzomys than species in some other genera are. Its sister group may be a clade of oryzomyines living in open or aquatic habitats, comprising, among others, Aegialomys, Nectomys and Sigmodontomys. Sooretamys angouya, also formerly in Oryzomys, is another relative; it has been placed in the same group as the species of Cerradomys in the past. The generic name Cerradomys is a compound of the word "Cerrado" and the Ancient Greek μῦς mys "mouse" and therefore means "Cerrado mouse".