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In order to analyze the effect of uneven spacing blade on the flow induced noise of centrifugal pump, a single-stage single-suction vertical centrifugal pump with six blades was chosen as the research object. Firstly, based on the theory of automatic rotor balance, three impeller models with uneven spacing blade were established, then with the purpose of extracting the dipole source of the wall of volute and leakage flow, the whole flow passage numerical simulation of model pumps was executed by applying CFD. The results of vibration simulation based on model response were compared with vibration experiment to verify the certain feasibility of NVH simulation, the simulation of hydrodynamic noise was further completed by applying BEM. The final work was to analyze the simulation results of the uneven spacing blade models and the original impeller model, the results showed that there were little differences in total SPL between uneven spacing blade models, which had lower total SPL and spectrum of SPL than original impeller model in general. New peaks of SPL were produced at 145 Hz and its harmonic frequency in uneven spacing blade models, except for the peaks of SPL at original blade frequency and its harmonic frequency, and the energy of noise was more disperse, the spectrum of noise was more stable. Compared with the other two models, the model with θ min of 50°could do better when considering the blade frequency and the characteristics of exterior noise at 145 Hz, and it had better noise performance. The results of the research can provide reference for further optimization of the noise of centrifugal pump.