Conical face-gear can be applied in coaxial torsional transmission configuration and improves the load sharing characteristic obviously. In this paper, a grinding method for conical face-gear with a worm wheel and the error compensation method of tooth surface are proposed. First, the space coordinate systems for meshing simultaneously of conical involute shaper, worm wheel and conical face-gear are established. By using a virtual conical involute shaper, the tooth surface equation of worm wheel is derived, and the tooth surface equation of conical face-gear generated by worm wheel is further obtained. Second, the causes and distribution of tooth surface errors of conical face-gear grinded by worm wheel are studied. The influence of tool parameters, worm parameters and machining parameters on tooth surface error of conical involute face-gear is studied. The results show that due to the half cone angle, the tooth surface error of the face-gear produced by the worm is approximately a high order curve along the tooth width direction, and the tooth surface error increases with the increase of the half cone angle. As a final step, a method of compensating tooth surface error is presented for face-gear by changing feeding path of the grinding wheel. Through compensation, the tooth surface error in grinding can be reduced by more than 90%.