In order to quantitatively analyze and reveal the present spatial distribution of soil erosion sensitivity, identify key areas for the loss of water and soil in Leishan county which belongs to the key ecological function area, and provide theoretical basis for comprehensive prevention and control of soil and water loss and ecological environment, this study selected the ALOS images in Oct 2010, and 1:50 000 topographic map which covers the whole Leishan county as the data source. Through using the geospatial information technology (RS and GIS) combined with 3D analyst grid calculation function, Leishan County’s DEM, slope gradient, slope aspect, land use and other main factors were extracted. By using ENVI software, combined with the normalized difference vegetation index model, the vegetation coverage was extracted. The spatial overlay analysis in ArcMap was used to divide water and soil erosion sensitivity level, quantitatively analyze its sensitivity in present situation, and reveal its spatial distribution. The results showed that: the slightly and highly sensitive area of soil erosion was 812.29 km2, accounting for 67.45% of total area in Leishan country, and the sensitivity of soil erosion was mainly slight in most areas of the county. The highly sensitive area of soil erosion was small, accounting for 5.96% of the total area. At the same time, there was a significant relationship between different elevation, slope aspect, slope gradient, vegetation coverage level and the sensitivity of soil erosion in the study area. The slightly and highly sensitive soil erosion area appeared single peak distribution which increased at first then decreased. The sensitive soil erosion area occurred mainly in the altitude range of 800 to 1 400 m, with the southeast and the northwest slope and the slope degree of 15 to 35, and the vegetation coverage level in 30% to 45%.