Abstract: New material of Pararhizomys from the Late Miocene Baogeda Ula Formation of central Nei Mongol are described, which is referred to P. hipparionumTeilhard de Chardin & Young, 1931 based on the size, morphology and dentine tract height of teeth. Pararhizomys are scarcely known from the area around the Mongolian Plateau chronologically from the early Late Miocene throughout Middle Pliocene. The genus is similar to Brachyrhizomys, Rhizomys and Tachyoryctoides in having a simple dental pattern, but can be distinguished from them by its absence of mesoloph(id)s and having only 2−3 reentrants on the molars. For expediently judging and comparing of this genus with others, an “H” index has been set for measuring the height of dentine tract of molars, and the lower incisor of P. hipparionum from Baogeda Ula was sectioned to observe the enamel microstructure. The dentine tract of Pararhizomys seems to have the gradually heightening and undulating tendency in its evolution, as the same in siphneids and arvicolids. The enamel microstructure of lower incisor of P. hipparionum is remarkably different from those of the rhizomyines Brachyrhizomys and Rhizomys and tachyoryctoididTachyoryctoides by the very thick inner portion of enamel and arrangement of prisms and interprismatic matrix. According to the morphology of cheek teeth and enamel microstructure of incisor, it seems that Pararhizomys could not be included in Rhizomyidae, and possibly represents a separate lineage. Pararhizomys andTachyoryctoides, restricted biogeographically within the Palaearctic Region appears to be adapted for temperate, arid and steppe environment, whereas Brachyrhizomysand Rhizomys are the typical factors of the Oriental Realm, living in a warmer, more humid and forested environment.