In order to study the effects of friction heat generation on thermal fatigue performance of brake disc during train braking,the relationship between friction heat flux distribution and brake pad structure was discussed,and a method of optimizing the brake pad friction blocks to improve the distribution of friction heat on brake disc was proposed.By finite element software ABAQUS,the braking process using the optimized brake pads and non-optimized brake pads was simulated respectively.The results show that the temperature of the optimized brake disc brake pads are decreased and the radial distribution of the thermal stress is more uniform along the brake disc.The results show that compared with the brake pads before optimization,the highest temperature and thermal stress of the optimized brake discs brake pads are decreased by 17% and 23% respectively.