According to investigation vegetation condition of grass and forest of three pieces of watershed in hilly region loess plareau in the third sub region and the distribution regulary of moisture, fertility, illumination, temperature in different slope land.

The insufficient water resources and ineffective use of limited precipitation in largearea already restricted the productivity of slope land and also affected the stability andsustainable development of this region economy.

Through experimental research on joint planting of trees and herbage to implement the return of cultivated land to forest and grass policy on alpine slopes in the Hezheng and Dingxi Counties of Gansu Province, the most suited establishment pattern for local conditions was screened out.

This paper analyzed the present situation of soil erosion in farm lands in hilly areas, emphasized the technological measures for the control and prevention of soil erosion and expounded the research progress and the achievements in application.