Abstract: In order to achieve the high-head, high-efficiency and non-overload performance in low specific speed submersible sewage pump, the WQS150-48-37 submersible sewage pump was designed with different design methods, and 3 optimization plans were obtained. The models were established using Pro/E software and Fluent program was applied to analyze the interior flow field and predict the performance of the pump under multiple loading conditions. The comparison between the predicted performance data and the tested results showed that a high efficiency, high-head, and non-overload design scheme can be obtained by increasing the blade wrap angle and diameter of the volute, reducing the blade outlet angle，controlling channel diffusion reasonably. The pump with new-type passage centrifugal impeller which broke through the traditional design had wider high efficiency area, steep head curve and better non-overload performance. This study can provide a certain reference for optimization design of high-lift non-overload sewage pump.