Abstract: Water environment is a sum of systems between aquatic creature and non-creature resources and relationships among subsystems around mankind, i.e.a compound of natural, society and economics. According to the present situation, eco-economic evaluation on water environment should pay great attention to the consistency of water environment and developments of regional economics, and to long-term macro-economic effect, social effect and ecological effect of regional water environment. The following principles should be obeyed in evaluations 1. the consistency of regional economic developments and environment, 2.the system being stable and orderly, 3.the whole maximum function of the system, 4.symbiosis (mutual benefit), and multiplicity, 5. cleanliness of water environment. In accordance with the above principles and characteristics of regional water environment,the author chose a criteria system including a series of the most important, most sensitive and quantified evaluation criteria, which affected and informed water environment.Econometrical method was also used in evaluation.