In order to further study the behavior of the disc brake in the braking process,based on the establishment of the simplified calculation model of the thermal mechanical coupling of the disc brake,considering the influence of temperature change on material physical properties and friction coefficient,the thermal-mechanical coupling characteristics of different initial braking speeds and braking pressures were analyzed by ANSYS Workbench,and the temperature field and stress field of the brake disc were studied from the radial,circumferential and axial dimensions.The results show that during the emergency braking of disc brake,the maximum value of temperature and stress is positively related to the initial braking speed and braking pressure.The initial braking speed and the braking pressure have great influence on the temperature field and stress field of the brake disc,and the influence of the braking pressure on the maximum value of the temperature and stress of the brake disc is more obvious than that of the initial braking speed.The temperature and equivalent stress of the brake disc are distributed in a circular band on the circumference,and they are consistent.The brake disc reaches the maximum temperature value earlier than the maximum stress value,and there is a coupling characteristic between them.The brake disc has large temperature gradient along the radial and axial direction,which causes a large stress change.The research results provide a reference for exploring the distribution of temperature field and stress field of brake disc and the thermal mechanical coupling characteristics of brake disc under different working conditions.