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In order to study the influences of different turbulence models on the hydraulic performance prediction of the mixed-flow pump, the mixed-flow pump model with a specific speed of 465 was selected and numerical calculation was processed by employing the standard k-ε, RNG k-ε, k-ω, SST k-ω turbulence models respectively based on SIMPLEC algorithm and unstructured tetrahedral grids. The head coefficient, the efficiency and the shaft power were predicted by the simulation and then compared with the test data. In addition, the pressure and the relative velocity distributions were also analyzed. The results showed that the performance curves predicted based on the four selected turbulence models had basically consistent trends with the test data curves. Among the obtained results, the prediction results based on the standard k-ε and RNG k-ε model were more close to each other and the prediction results based on the k-ω and SST k-ω model were more close to each other. For the head coefficient and the efficiency, the prediction results based on the k-ω and SST k-ω model were more accurate under （0.6~ 0.9）Qd and the prediction results based on the standard k-ε and RNG k-ε model were more accurate under （0.9~1.3）Qd . For the mixed-flow pump model designed, it could be ensured that the performance prediction accuracy was within ±5%, which could meet the requirements of engineering calculation, by choosing k-ω model under （0.7~0.9）Qd and the standard k-ε model under （0.9~1.2）Qd .