The 3-D K-ε dual-model equation was adopted to simulate the inner flow field of the centrifugal pump, while the optimization measures such as the method of increasing flow of the pump and so on were employed. A high-lift, high-speed, ultra-low specific speed and high-performance centrifugal pump for LRE was designed with FLUENT flow calculation software and GAMBIT predisposing software by adopting the appropriate optimum measures. The results of hydraulic test indicate that the performance of the pump is excellent, and the optimal design method based on the computation of the centrifugal pump inner flow field is feasible and efficient.