Abstract: A client is more important than a developer in major issues like specification and modification of goals and functions of an environmental information system,project design and management of development.Inaccuracy in identifying the client of the system is largely responsible for some of the environmental information systems in China that nobody is using after their development.Involvement of high level persons,dynamic involvement and investment of sufficient resources are imperative means for a client to play his or her roles.Systems analysis should not only satisfy current demand of the client but also should assist the client in properly restructuring channels for information flow and means for information collection.Development of an environmental information system should adhere to principles of few and good,establishing goals on realistic ground and correctly handle relations among training,utilization and maintenance.