Abstract: In response to the increasingly strict sewage discharge standard, a sewage treatment plant in Suzhou has ensured the water quality concentration of the sewage treatment plant by carrying out low-level operation of the sewage pipe network and continuing to promote leak detection and repair. The concentration of COD was more than 300mg/L and BOD₅ more than 120mg/L. By analyzing the characteristics of influent water quality, the whole process according to different characteristics of influent water quality would be optimized, so as to maximize the utilization of organic carbon sources in sewage. At the same time, the sewage treatment plant continued to strengthen the information transformation, and carried out the constant water volume and constant water level system transformation of the inlet pump room. After the transformation, the total energy consumption decreased by 2.2%. The biological section adopted an automatic aeration system, and the power consumption of the blower decreased by 12.92%. The electricity consumption of oxygen-consuming pollutants per-unit has decreased by 15.51%.