Based on defining the constraint and boundary conditions between parts and setting the key parameters such as brake friction coefficient, convection heat transfer coefficient and rubber bushing stiffness, a complete transient thermomechanical coupled finite element model considering brake disc, friction linings, back plates, piston, brake caliper, bracket, guide pins and rubber bushings, was established. By using this model, the thermomechanical coupled characteristics, such as temperature, circumferential stress and deformation, under single braking condition of disc were analyzed. In further research, it is found that the function of pin rubber bushings is equivalent to springs but can not be ignored as fixed restraint. The model was verified by thermomechanical coupling test on brake inertia test bench. The results of thermal imager and other equipment show that the brake caliper has an important influence on the thermomechanical coupled characteristics of the brake.