Abstract: Since the first discovery of mammalian fossils in 1964 from the Leijiahe area, Lingtai, Gansu, there have been three field teams working there on the "Leijiahe Formation", which developed on the Cretaceous limestone and before accumulation of the Loess. This Formation was thought to be of Pleistocene (Huang et al., 1979), Pliocene (Huang et al., 1993) and Late Miocene to Early Pleistocene (Zheng, 1994) respectively. In 1998— 1999, financed by the NSF we did more detailed biostratigraphic works on three sections, namely, Loc. 93001, 93002 and 72074(4) section (Zheng and Zhang, 2000; Zhang and Zheng, 2000, 2001). The present paper gives synthetic analysis with small mammals from the three sections and comparison with some faunas from North China.