Based on the theory of tire cornering and tire force research, the effects of load re-distribution on the tire cornering characteristics and the effects of side angle on the vehicle steering characteristics were analyzed. Some adjustments were made to Ackermann theory based on the actual situation, and the contrast shows that this method can reduce the error of the design and the actual situation. Finally, the steering wheel system of 220t electric mining truck was optimized by experiment, which can significantly improve the vehicle steering system and vehicle motion characteristics performance.