The Ailuropoda-Stegodon fauna is a typical mammalian fauna in South China during the Quaternary. The common species mainly live in the subtropical zone, but some tropical species mainly distribute in tropical zone to south-subtropical zone, such as Pongo, Hylobates, Elephas maximus, as well as living species of Megatapirus augustus and Rhinoceros sinensis, indicating a forest environment with the south of mid-subtropical climate features. Based on the determination of faunal composition and geographic distribution characteristics during the OIS 5e in South China, we mainly depend on the distribution of tropical species and their far-north living boundary, and inferred that the north boundary of the mid-subtropical zone stays to the south of Qinling-Huaihe line of China, namely, it is three latitudes further northwards than today, and the temperature is about 4~5℃ higher than today in January, and annual temperature is 3℃ higher than average temperate. It suggests that the mid-subtropical climate or tropical climate possibly prevails at present subtropical zone,which indicates the great evolution of bioclimatic belt. The occurred event corresponds to the high temperature period and the peak of Solar radiation at 35°N in the winter-half year, which probably result from the global climate changes.