Abstract: The social-economic web survey and water environmental data of 35 cities in 2010 of Huaihe River Basin are adopted in the study.On the basis of highlighting the dominant factors and the operational principle, entropy value method system is chosen to construct the comprehensive evaluation system of prevention and control for water pollution. Entropy weight method is adopted to evaluate water pollution control ability of cities and the GIS spatial analysis method is used to explore the overall and partial spatial difference, characteristics and laws of water pollution prevention and control in Huaihe River Basin, and classify the prevention and control ability of the basin.The results show that: ① The prevention and control ability for water pollution is generally low in Huaihe River Basin, and presents significant spatial difference. The basin on the whole shows step trend of the prevention and control ability, main stream higher than tributary, downstream higher than midstream, midstream higher than upstream. ② In the basin, the control ability of the economically developed area is obviously higher than that of the less developed regions, the capital cities much higher than the ordinary cities. ③ The comprehensive control ability for water pollution of the river basin highly matches with the actual measurement of water quality spatial distribution. Generally, water quality is good in the regions with high control ability, and poor in the regions with low control ability.

Key words: prevention and control pollution, spatial diversity, the Huaihe River Basin, water environment