In view of the characteristics of wastewater produced by Xinyuangou aggregate system of A′hai Hydropower Station,a processing scheme of 2-level settling,sludge dewatering by machine,and reuse of clarified is adopted,in which,the natural sedimentation is in the first level settling and coagulation sedimentation is in the second level,and rubber belt vacuum filter is used for sludge dewatering.During 1 year of operation,the system has the advantages of low cost,meeting requirements of environmental protection and water reuse,realizing the integration of economical benefit and environmental benefit.The design and application of wastewater treatment system is presented.