This paper takes 63.5 # vulcanizer as an example, which is used to vulcanize 12R22.5 tires. The main work is the structure design of tire mold. Use ANSYS finite element simulation software to analyze the temperature characteristics and stress of tire mold. Setting structure optimization target of tire mold according to production requirements. Analysis of data before and after tire structure optimization to verify the optimization effect. The results show that, after the structure optimization, the mold temperature time is shortened by 1.3 h, the maximum stress value is reduced by 4.9 MPa, the average temperature of the inner contour of the pattern block is increased by 1.8 ℃, and the temperature uniformity and symmetry are improved.