Jialingjiang river is one of major-soil erosion watershed of the Yangtze river, its basin area and average annual runoff account respectively for 15.8% and 15.6% of the total amount of the Yangtze river upstream the Yichang hydrologic station, but its sediment production accounts, for 25.5%. Severe soil erosion is not only a big threat to the downstream ecological environment but also a critical factor in the future operation of the Three Gorge reservoir. Therefore, the government has already been developing a number of soil and water conservation projects in this watershed since 1989. Its two main upstream tributaries Bailongjiang and Xihanshui are the most severe soil erosion prone areas, which were selected in this study. Two time series of Landsat TM images in 1992 and 1996 were used to investigate the dynamic variation of soil erosion in the area. An Arc/Info GIS based dynamic spatial information system was developed for data storage and manipulation with its user interface compiled with GeoMedia and Visual Basic.