Abstract: The first climatic type distribution map of desertification in China has been drawn out making use of Thornthwaite method which was recommended in International Convention to Combat Desertification.On the map,the potential extent of desertification in China has been outlined.The results show that among the 3 317 032 2 km² potential areas,there are 751 161 9 km² distributed in semi humid prone to aird area,1 139 214.2 km² distributed in semi arid area and 142 665 1 km² in arid area,and their proportions to territory are 7.8%,11.9% and 14.9% in order.The potential extent of desertification in China cover administrative divisions of 18 provinces and 470 counties and consists of 34.6% of the territory.

Key words: Desertification Convention, Thornthwaite Method, Potential evapotranspiration