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In order to improve the hydraulic design of flowingpassed components of the jet centrifugal pump (JCP), the performance of rotorstator interaction on the hydraulic performance and its acoustic response characteristics of the pump were optimized. The multiobjective optimization design of rotor and stator matching was carried out by orthogonal experiment and computational fluid dynamics/computational fluid acoustic (CFD/CFA) technology. Some relevant geometric parameters of impeller and positive guide vane of JCP were considered in the test design. The effects of water head, efficiency of JCP and hydrodynamic noise in the rotors and stators were analyzed according to the impeller blade number, impeller blade profile, guide vane blade number, guide vane blade profile and clearance of rotor and stator. Multiobjective optimization scheme was determined by matrix analysis method, the optimal matching combinations of rotor and stator cascades were obtained. The results showed that under the rated conditions, after optimization, the water head remains unchanged, hydraulic efficiency was increased by 0.5 perantage points, and the overall noise in the rotor and stator cascades was decreased significantly, the impellerinduced noise was decreased by 7.1% and the guide vaneinduced noise was increased by 2.2%. It was verified that determining multiindex optimization scheme by weight matrix analysis method was feasible. The key of the design of low noise JCP was to determine the clearance between stator and rotor as well as the blades number of stator and rotor. Different matching schemes of rotor and stator cascades were more sensitive to the water head of JCP than to its efficiency, and more sensitive to the guide vane induced noise than to impeller induced noise，at the same time, the unsteady flow in guide vane influenced by rotorstator interaction was more obvious than that of the impeller. Dipole source noise was caused by pressure pulsation on the flowingpassed wall. The frequency spectrum characteristics of guide vane induced noise are basically the same as that of pressure fluctuation, but the frequency spectrum characteristics of impeller induced noise are obviously different from that of pressure fluctuation.