Quanjiagou comprehensive experimental area was established by the Institute of the Loess Plateau Control of Shannxi in 1979. The remarkable. changes in ecology and economy have taken place as the structure of land utilization and estate has been rationalized. The mean net income increased from 118 yuan in 1979 to 707 yuan in 1992， the control degree raised from 32 percent in 1979 to 71 percent in 1992，soil erosion mudulus has been reduced from 16 279t/km² before 1979 to 2330 t/km² during "The Seventh Five-year Plan". Ecological environment has been improved remarkably; the farmers' living standards have been improved stably; and remarkable benefits for society and economy have been achieved. But，some notable problems still exist，such as how to stabilize forage area, how to renew low beneficial forest land, and how to manage projectical measures of soil and water conservation. So some ways to resolve these problems were presented in this paper, such as la如ng particular stress on the benefit of soil and water conservation, strengthening scientifical control，adjusting service mechanism，changing free input to return or economic service,etc.