3D topography of the gear tooth surface was simulated by using MATLAB，and threedimensional morphology of lubricating oil film was established based on MATLAB programming.The oil film pressure of tooth surface was calculated by numerical analysis method of elastohydrodynamic lubrication.The experience formula of oil film pressure was established according to the MATLAB calculation of tooth surface lubrication based on the orthogonal experiment scheme.The results show that 3D surface topography of the gear tooth surface simulated by MATLAB has a high consistency with the result of experimental measurement,and 3D topography of lubricating oil film simulated by MATLAB is in good agreement with the actual lubricating oil film distribution law.The error is less than 10% between the measured maximum oil film pressure by experiment and the calculation value.The relationship between the value of oil film pressure and the surface morphology presents negative correlation,and has a good consistency.The proposed method can be applied to the prediction of threedimensional morphology of tooth surface oil film.