The social,economic and environmental proBlems brought by Three Gorges Water Conservancy Project have been concerned by the whole China and the world,and the barrier belt in the Reservior area is the area which causes most contradiction between land and local residents.Taking Wanzhou District of Chongqing as an example,this paper uses TM remote sensing image data and DEM data to extract hydrothermal change line before and after Three Gorges Reservoir retained water during 1995-2008,conducts research on comprehensive division of ecological barrier based on ridge line extraction under GIS support and analyzes slope distribution and land exploitation situation in barrier belts.The results show that after the Reservoir retained water,the temperature level and humidity level of the two banks of the Reservoir are affected by the rise of the water level in the Reservoir,that the affected area includes inside 30 km of the two banks of the Reservoir,that prescriptive barrier belt scope of Wanzhou District mainly covers inside 30 km of the two banks of the Reservoir,that prescrilptive barrer belt scope of Wanzhou District mainly covers inside 35km in the south bank and the north bank of the Reservoir water level,its tota area is 2215 km2 and the barrier belts 64.2 percent of the total area,that unreasonable land exploitation exists in brrier belt of Wangzhou District,and that the slope planting land and constructing land in the District is easily breaking the ecologcal environment which is originally very vulnerable and which derectly threatens the operation of the Reservoir.This research result can provide reference for comprehensive research on barrier belt of Three Gorges Reservoir area.