As the increasingly serious contamination of source water as well as the more stringent water quality standard, the pretreatment and advanced treatment were required for water supply enterprises.To find an appropriate treatment, the traditional approach is normally based on experts' knowledge and their experience which has several shortcomings.In order to find an effective and efficient way coping with the issue during selecting the optimal technologies for water treatments, an improved analysis hierarchy and fuzzy evaluation model was proposed.With the model, multistage fuzzy synthetic judgment was adopted with the Improved Analysis Hierarchy amended by Accelerating Genetic Algorithm.The application of this model had been introduced for the selection of supply water treatment technologies in a particular waterworks in Chongqing.