By analyzing the ISO3450，the minimum requirements for braking performance to be satisfied for offhighway dump truck were obtained. The service brakes distance was up to 114 meters as required. The corresponding braking torque was calculated and determined for the initial implementation scheme. Various work conditions according to the concrete scheme of brake were checked, and the final performance results by calculation were confirmed. Aiming to the analysis of thermal mechanical coupling brake disc of one 100 tons mining dump truck, in the performance and load the material disc aspect, the analysis of temperature field, stress field and thermal expansion of the friction pair was carried out, and verification of the braking performance of the vehicle in full cycle was passed. The results show that the braking system fully meets requirements, so the overall brake performance of the vehicle is ensured.