Abstract: The authors briefly discuss the relationship between major environmental issues and technical decision\|making factors such as site selection,trailed wastewater draining,treatment process and technologies,and service areas of municipal wastewater treatment (MWWT) projects,and provide a partition of environmental assessment for planning and project levels of MWWT.It is recommended that the stratgeic issues such as site selection and wastewater draining should be evaluated during the planning stage,while more attention should be paid to mitigation measures for minimizing effects during the feasibility study.