Abstract: The conventional methods for determining the tooth geometry and tooth contact of spiral bevel gears are based on differential geometries of rigid body movement,and consequently make description of tooth surface and analysis of tooth contact behavior very complicated.In this paper,the authors work out a digital simulation method for tooth cutting and meshing of spiral bevel gears.A numerical model of tooth surfaces is set up by digital simulation of tooth cutting.The analysis of tooth contact behavior is completed with the numerical model of tooth surfaces.Solution of the meshing equation v·n=0 in conventional methods is replaced by minimizing the normal distance between points on the tooth surfaces in our method.The results of digital simulation for the spiral bevel gears used in a Chinese aeroengine show that the presented method describes the tooth shape and tooth contact characteristics more conveniently and efficiently,and can determine optimal cutting adjustment parameters for obtaining spiral bevel gears with good contact quality.