Safety and environmental problems caused by coal mining and utilization are becoming increasingly serious. Studies in the coal spontaneous combustion characteristics based on constant temperature difference guidance method, which is of great significance for mine safety prevention and environmental protection. In this paper, a new method, Constant Temperature Difference Guidance Method, was developed in this paper for studying coal spontaneous combustion characteristics. By creating a constant temperature difference between coal temperature and ambient temperature, self-heating of coal is guided in this new method, which largely improves the efficiency and success rate of coal spontaneous combustion testing. Through analysis, this method was proved capable of providing a comprehensive description of coal's low-temperature oxidation characteristics. Besides, through changing different values of the temperature difference, various factors of low-temperature coal oxidation under adiabatic environment can be calculated. Additionally, spontaneous combustion point and ignition point can be obtained by analyzing time-temperature curve of coal oxidation. These two points along with the duration to achieve these two points were used in this paper to develop a risk index for evaluating coal spontaneous combustion propensity. (C) 2019 Published by Elsevier B.V. on behalf of Institution of Chemical Engineers.