Three typical work conditions were chosen to analyze the forces of steering axle housing of wheeled combine harvester. The effect of different section forms of wheeled combine harvester on strength and rigidity of steering axle housing were studied. Then, the optimized design method of steering axle housing was put forward. The strength and rigidity of steering axle housing for a certain type wheeled combine harvester were analyzed in ANSYS. Meanwhile, its section forms and dimensions were optimized. The improved steer axle housing not only satisfied the demand of strength and rigidity, but also reduced its weight by 17.8%, and enhanced its manufacturability at the same time. The reasons for stress concentration were studied and the optimization processes were proposed.