Gear couplings are usually machined using hob and slotting cutter in a predetermined circular path. The tool feed path determines tooth profile. This article designs a new feed path. A new mathematical model of tooth surface is constructed based on path and tooth profile parameters. Calculation method for minimum normal design clearance is proposed, and furthermore, theoretical model for the clearance under misalignment conditions is developed. The calculation of the tooth surface coordinates and minimum clearance in the circumferential direction, the distribution of the minimum clearance in the circumferential is studied under the new path. The clearance of the tooth surface and circumferential direction are obtained, and the contact characteristics of teeth in the circumferential direction are analyzed. The results show that the new path can reduce the dependence of misalignment angle on clearance and tooth width compared to conventional path. A high load-carrying contact with full involute is more easily achieved on the tooth surface, and the load-carrying performance are more evenly distributed across the teeth.