Abstract: The traditional design of gear hobbing fixtures relies heavily on accumulated experience and trial-and-error methods, lacking systematic analytical approaches, which results in protracted design cycles and elevated costs. To address this challenge, a set of quick-change hobbing fixtures was developed specifically for a disc-type gear using finite element analysis (FEA) tools, thereby enhancing the overall design level and mechanical performance of the fixtures. The fixture structure was designed based on the machining principles of cylindrical involute helical gears via hobbing. Simulation analysis was conducted utilizing ANSYS Workbench software. The analysis results indicated that the structural strength of the fixture met the machining requirements, but the equivalent stress value on the expansion sleeve exceeded the allowable stress by 24%. To improve the equivalent stress distribution on the expansion sleeve and enhance its service performance, a multi-objective optimization method based on a genetic algorithm was employed for its redesign. Following optimization, with both deformation and equivalent stress satisfying the required criteria, the fatigue life of the expansion sleeve was increased from 594.7 cycles to 6 666.3 cycles.