Abstract: Through the numerical simulation of the shaft inlet channel of a pump station, it is found that the flow separation phenomenon occurs at the confluence of the shaft tail. From the perspective of the line shape and size of the shaft tapering section, 15 optimization schemes are designed to study the hydraulic performance of the shaft inlet channel and the flow separation phenomenon at the confluence of the shaft tail. The optimal scheme is studied by the model test. The results show that the flow separation at the tail confluence of the shaft inlet channel will reduce the weighted average angle of the outlet section velocity of the channel. Under the same linear scheme of the shaft tapering section, the hydraulic loss of the shaft inlet channel first decreases and then increases with the increase in tthe shaft tapering section length, and the velocity weighted average angle gradually increases with the increase in the shaft tapering section length. When the linear optimization scheme 2 is adopted, there will be no flow separation at the confluence of inlet channel and shaft tail. Among the 15 schemes, the hydraulic performance of the inlet channel of scheme JS14 is better, which is the preferred inlet channel scheme for a pump station. The maximum efficiency of model test of pump device adopting scheme JS14 can reach 77.57%, and the numerical simulation of the hydraulic loss in the inlet channel of the device is consistent with the model test.