Based on the orthogonal experiment of grinding orthogonal face gears with butterfly grinding wheel, an analysis has been conducted on such grinding parameters as grinding depth ap, grinding wheel speed vs, and the influence of tool feeding speed vw on surface roughness Ra, grinding depth h and removal rate Zw, thus obtaining the optimal grinding process parameters. According to the results of orthogonal test, the regressive mathematical models of grinding surface roughness Ra, metamorphic layer depth h and removal rate Zw can be established by adopting regression analysis method. The results show which testifies the better precision of these models, thus providing some theoretical basis for the improvement of grinding gear quality and efficiency.