In order to enhance the bearing capacity,the double generating angle tooth profile for the oval gear pair used in unidirectional and continuous transmission occasion is designed. Based on the generation cutting theory,the pure rolling mathematical model that the center line of double pressure angle asymmetrical rack roll along the oval pitch curve is deduced. The secondary development technology of three- dimensional software is used to realize the digital modeling of oval gear pair,and then the kinematics and mechanical analysis are conducted. As a result,the designed double meshing angle oval gear pair can meet the transmission requirement and have good mechanical ability,which has well reference to the bearing capacity improvement of other non- circular gear pair.