Because of the degradation of the thermal control coatings in harsh space environment, the error between the real parameters and the design parameter must happen. However, calculating the satellite’s temperature and infrared radiation repeatedly was time-consuming. Firstly, based on the simulation experimental data, the degradation model of the thermal control coatings was established. Then, the temperature sensitivity and infrared radiation sensitivity formulae of the surface node of the satellite were derived, according to the calculation model of the temperature and infrared radiation. Combined with specific satellite’s parameter, the temperature sensitivity and infrared radiation sensitivity were calculated. The result shows that the change of infrared radiation caused by the degradation of the thermal control can be analyzed by using the infrared radiation sensitivity directly to avoid the repeat calculation of the satellite’s temperature and infrared radiation.