The abrasive flow precision machining(AFPM) method is utilized to smooth the inner wall of the valve sleeve. Through the method of large eddy simulation(LES) and a reasonable subgrid model, numerical simulation analysis is performed on the inner surface of the abrasive flow machining (AFM) valve sleeve to predict the material removal efficiency and surface quality. The effects of wall shear force, dynamic pressure, particle pressure, and vortex on the particle flow are analyzed under different processing parameters. The mechanism of precision machining of the inner wall surface of the valve sleeve by abrasive flow is obtained. The experiment of AFPM was performed by response surface methodology. The results show: The processing pressure and the number of abrasive mesh have a significant impact on the AFM. Through the quadratic response surface plot and contour plot, it is found that the roughness has a minimum point and the best process parameters are obtained. After AFPM, the roughness of the inner wall of the valve sleeve can reach 0.218μm. Finally, the roughness prediction model is established by using the analysis of variance method, and the quality control method of the inner wall surface of the valve sleeve is obtained.