Abstract: According to the characteristics of urban water supply, the indices of performances evaluation were proposed for relevant enterprises. Then, an agent-based democratic evaluation system was suggested for different water supply enterprises, which has been applied to such enterprises in 13 cities of China. This evaluation takes full account of the natural value orientation of each and very enterprise, while the public value orientation is not neglected. So, it is able to not only reflect the individuality of an enterprise in evaluation but also avoid the divergences which were often found in the weights for evaluation. The results of applications with examples given showed that the simple evaluation system proposed can reflect quantitatively the performances of urban water supply enterprises actually.