The reasons that reforesting had played an important function in the engineering of converting the farmland into forest（ECFF）were the seven limiting factors of that the climate, the site conditions and so on in Liangshan prefecture. Based on the theory of vegetation restoration and the rules of production structure’s adjusting， the reforesting should follow the seven rules of that trees fit site conditions, adjusting and optimizing the structure of tree species and forest stand，and so on in the ECFF of Liangshan prefecture. Reasonable arrangment, actualizing year by year and 5-8 years’efficiency protection will be the plans to increase the forest cover rate of Liangshan prefecture by 0.8%，and at the same time to unify the ecological effects，the social effects and economical effects together.