Abstract: This is the 2nd report on the Yagou mammalian fauna following the article on the giant rhinoceros fossils published recently by the present authors (Qiu et al., 2004). Except two species of giant rhinoceros, eight forms were reported here: Tsaganomys altaicus, Megalopterodon sp., Schizotherium ordosium, Hyracodontidae gen. et sp. indet., Ardynia altidentata sp. nov., Ardynia sp., Aprotodon lanzhouensis, and Paraentelodon cf. P. macrognathus.