Abstract: The full implementation of Gansu Dingxi forests the past 10 years, has achieved remarkable results. In this paper, key areas of returning farmland to forest stability Dingxi City area as an example, through the collection, field surveys, sampling and laboratory analysis, comparative study of different vegetation types with returning control to (agricultural land and natural grassland) of soil physical properties changes. Including soil water content, bulk density, soil porosity, soil water-stable aggregates structure. The results show that: the natural grassland and highest water content of Tamarix were 13.44% and 13.52%. Apricot of farmland and water content as low as 8.01% and 8.2% respectively. 0-60cm soil layer in different caragana little change in bulk density and the smallest, the largest changes in upper and lower fields. 20-60cm in returning farmland to forests and the porosity is higher than the natural grassland and agricultural land, natural grassland and farmland non-capillary porosity changes in small and large up and down is not conducive to soil infiltration. Robinia pseudoacacia, Caragana, Tamaricaceae of water-stable aggregates the content of most agricultural fields were 3.4,2.8 and 2.4 times. After returning farmland to forest, woodland soil physical properties have been significantly improved, and agricultural land and natural grassland as compared to black locust, improved Peashrub best. Therefore, returning farmland to forest areas during the recovery process of vegetation to the soil depth understanding of local environmental characteristics, so the light of local conditions, appropriate and suitable tree.