Beginning with Navier-Stokes equations, the flow field is described in laminar-flowmodel which is solved by SIMPLE method in Euler coordinate system. Considering the compli-cated boundary conditions of blades, the finite element method is used in flow analysis. Theprocedure is programmed with FORTRAN language. The flow field in the impeller of theSanxia hydraulic turbine with mixed flow is numerically simulated to get the distributions of ve-locity and pressure in the impeller,