According to the rule of volume constancy, forming process of half shaft bushing was analyzed, the roughcast was calculated conversely, and the hot extrusion process was established. By combining with the rigid-viscoplastic finite element method (FEM) theory and using FEM software, a 3-D thermodynamic coupling simulation was performed for the reverse extrusion process of half shaft bushing. The major processing parameters, which influence the hot extrusion of half shaft bushing, include extruding temperature, extruding velocity, warming-up temperature of dies and so on. The simulation results corresponding to different extruding temperatures, extruding velocities and warming-up temperatures of dies, were analyzed and compared with each other. Finally, the influence of processing parameters on the half shaft bushing was obtained, and the rules of metal flowing during the reverse extrusion process of half bushing were disclosed. The producing application of optimized forming parameters can enhance the half shaft bushing's forming property and economy performance.