An axial force estimation is a crucial problem in the design of a deep well pump. According to the cost of time and financial resources by experimental measurement and low precision and applicability of using experiential formulas, the effects of solid modeling, mesh generation, residual convergence precision, turbulence model and numerical solutions on the accuracy of numerical simulation were investigated. And the best scheme was applied in the numerical simulation to predict the axial thrust of the deep well pump. The simulation values of axial force are in agreement with the testing values, and the maximum error is less than 10%.