Soil erosion of hilly areas in the Sichuan Basin is more serious than any other regions in Sichuan Province, and it is an important reason that ecological environment is deteriorating, natural disaster is frequent, rural economy is laggard and people living conditions are hard. Based on the serious features and induced factors of soil erosion in hilly areas of Sichuan Basin, this paper probed into the causes and harm of soil erosion including destroying ecological environment and farmland resource, sedimentation of rivers and lakes, deterioration of flood and drought disasters, reduction of the soil fertility and the capacities of the water storage and drought resistance. Therefore some controlling countermeasures are put forward in order to further control soil erosion and improve the ecological environment, such as ecological environment construction, overland flow improvement, farmland construction and population management. So the land can be reasonably exploited and utilized and utilization ratio and productivity in the purple sand shale hilly areas can be improved. These are not only neccessary for the economic development in hilly areas in Sichuan Basin, but also has grand practical significance and profound influence to improve ecological balance of the Yangtze River watershed.