Abstract: The existing researches do not consider that coal of different particle sizes in the goaf is affected by the axial stress generated by the collapsed coal rock and the residual coal pillars, which will cause major changes in the coal permeability, fracture structure and other parameters, thereby affecting the temperature rise process of coal spontaneous combustion and oxidation. In order to study the temperature rise characteristics of spontaneous combustion and oxidation of coal with different particle sizes under the effect of thermal-stress coupling, the change law of the temperature rise rate, oxygen consumption rate and heat production rate of coal with different particle sizes is measured by using load-and-pressure coal spontaneous combustion characteristic parameter measuring device and a gas chromatograph. The experiment show the results as follows. ① The temperature rise rate of coal samples of different particle sizes under different uniaxial stresses has a consistent trend with the increase of temperature, and the overall trend is to increase first and then decrease. When the uniaxial stress is 2, 4, 6, 8 MPa, as the particle size of the coal sample increases, the maximum temperature rise rate first increases and then decreases. When the uniaxial stress is 10 MPa, the maximum temperature rise rate increases with the increase of particle size. ② The oxygen consumption rate of coal samples with different particle sizes increases rapidly and then increases slowly during the temperature rise process. The oxygen consumption rate of coal samples with different particle sizes generally tends to increase with the increase of uniaxial stress. ③ The overall heat production rate of coal samples with different particle sizes tends to remain stable first and then increase and then decrease during the temperature rise process. As the particle size of coal samples increases, the maximum heat production rate of coal samples under appropriate uniaxial stress is greater than that without uniaxial stress.