Abstract: The Ordos Plateau showed the famous Salawusu and Shuidongou Paleolithic sites discovered firstly in China and is the key area for studying human evolution in eastern Asia. The Wulanmulun site is located at the bank of the Wulamulun River in the Kangbashi New District of Ordos city. Many stone artifacts, mammalian fossils, and charred woods was obtained from the site. The 14C ages of the remains are 41.4~33.1 cal ka BP corresponding to the MIS 3 period. The evidence from pollen and charcoal fossil indicates that the shrub-steppe appeared in the early period and the typical steppe grew in the late period. The climate is dry and cool but warmer and wetter than today. Shrubs and small trees such as Elaeagus and Zygophyllum are used as fuelwood by ancient people. The relatively warm and humid climate in MIS 3 period was conductive to human reproduction, diffusion and exchange, which is probably an important reason of “The upper Paleolithic revolution” in North China.

Key words: Ordos; Wulamulun; MIS 3; Vegetation; Environment