Abstract: In order to establish the design method of the liquid-ring pump with splitter blades so that improve the efficiency and inlet vacuum of the liquid ring pump, the formulas of blade number, the offset angle of the inlet and outlet of the short blade and the diameter of the inlet and outlet of the short blade were obtained by theoretical derivation. The accuracy of design theory was verified by using the method of combining experiment and numerical simulation. Compared with the original model, the efficiency of the liquid-ring pump with splitter blades at 0.02, 0.035 and 0.05 kg·s^–1 is increased by 2%, 1.4% and 4.3%, and the vacuum is increased by 4.12, 3.1 and 2.21 kPa. The internal flow field distribution of the liquid-ring pump with splitter blades designed according to this method is more uniform, the flow loss in the pump is reduced. The liquid-ring pump with splitter blades designed by this method has great hydraulic performance.