The process of grading soil erosion potential danger and its spatial distribution of Changchun city is carried out in ARCGIS 8.3.Firstly,soil erosion modulus is estimated using USLE and maps of soil density and soil horizon thickness are derived from detailed soil survey data.Then,the year that can be eroded of soil thickness is calculated using soil erosion modulus,soil thickness and soil density.In guideline with Ministry of Water Resources' classification standards,the potential danger of soil erosion is divided into five grades and the index of soil erosion potential danger(SEPDI)is established.By using GIS,the authors analyzed the soil erosion potential danger under different erosion background such as different gradient level,different aspect,different geomorphology type,different land use type etc.,and thus discussed the distribution characteristics of soil erosion potential danger.