Abstract: Fluid flow in mixed flow thrust and its performance characteristics are studied through numerical simulation. Three-dimension grid is shaped in body-fitted coordinates for the fluid calculation and turbulent flow is simulated by standard k-epsilon two equations. At the same time the SIMPLEC algorithm is applied to solve its intense turbulence of fluid phase. Performance characteristic of the impeller passage is predicted, with the conclusion is preferably consistent with the testimony. In addition, through the analysis of flow velocity and pressure, impact flow and countercurrent flow are found, offering foundations for further research on water thrust mixed flow pumps.