In order to adapt the construction condition of a long row of shore distance for cutter suction dredger，on the basis of the original high efficient and high-pressure dredge pump with three blades on 6 500 m3/h cutter suction dredger，ensuring the shape of impeller unchanged and capacity of impeller passage no decline，we design the axial plane and the shaft surface streamline of the impeller，propose the four twisted blades impeller，calculate the optimization for the blade wrap angle combining with numerical simulation，determine the blade angle as 138°，verify the hydraulic performance of the pump by comparing the test results with the simulation results through the model pump test，and predict the productivity and energy consumption under the condition of different soil，the different row of shore distance by comparing the new impeller with the original impeller with three blades. The results show that compared with the original impeller with three blades，the four blades dredge pump lifts up by more than 18 m，the highest water efficiency reaches 86%，and the through particle sizes of the two impellers are both 425 mm. With 0.2 mm fine sand，the productivity of the dredge pump increases by more than 9%，the row of shore distance increases by more than 14%，and the minimum energy consumption reduces by about 3.5%.