Abstract: The loess plateau of northern part in Shanxi Province is consisted of hills and upland with 200--300m of different relative altitude, and where the vegetation doesn’t show the characteristic of the vertical zone. According to the distributed northern border of the quercetum, the demarcation line between the forest zone and the Steppe zone shown as the following:Qinjan--Ansai-Zhidan-the south of Wuqi. Quercetum is typical in the south of this line, which is the part of Huabei deciduous broad-leaf forest region, From this line to Chang-Cheng and Yu-Ding highway, it belongs to the forest-steppe zone.