A new structure of radial-bias tire carcass was discussed in this paper．A three-dimensional finite element model of the radial-bias tire was established using Abaqus and the grounding performance of the tire and mechanical properties of the reinforcement materials were analyzed. The results showed that，by improving the radial stiffness of sidewall and controlling deformation of shoulder，the shoulder stress concentration of radial-bias tire could be reduced，the uniformity of tire ground pressure distribution was improved，and the distortion of tire cross-section profile could be avoided，which could enhance tire load capacity，wear resistance and steering performance.
