With the use of the RNG k-ε turbulence model and the SIMPLEC algorithm, as well as after the secondary development of the software Fluent, the velocity field and pressure field of a axial flow impeller were numerically simulated in the single-phase (clear water) and the solid-liquid two-phase conditions. The distributions of pressure, velocity and solid concentration in the impeller under the single-phase flow and the solid-liquid two-phase flow conditions were compared. This study has shown that the numerical simulation results are the same as the actual situation.