<p>Oxidized coal in the oxygen-poor environment of goaf is prone to reignite. This jeopardizes the production safety of coal mines. Therefore, in order to simulate this process, the coal is heated to 60, 90, 120, 150℃ through the thermogravimetric (TG) and differential scanning calorimeter (DSC) and continuously injected with oxygen concentration of 5% oxygen nitrogen mixture gas. In the process of coal reignition, the quality and heat of oxidized coal show phased changes, which can be divided into (I: water loss and degassing; Ⅱ: oxygen gain mass; Ⅲ: decomposition by heat; Ⅳ: burning) four stages. The pre-oxidation process only prolongs the reaction time of stage IV. The mass loss of pre-oxidized coal at low temperature is less than that of raw coal, while the reverse is true of high temperature coal. As the temperature of pre-oxidation rises, the amount of heat that oxidized coal absorbs drops. Except for P-90, the total heat release is higher than that of raw coal. By introducing the ratio of mass to heat change (q·m⁻¹), it is found that the quality and heat change of coal samples are synergistic. The results of the kinetic study indicate that the average activation energy of oxidized coal first reduces and then increases in stage II as the primary oxidation temperature rises. Stage III sees an increase, a fall, and a subsequent increase in the average activation energy of oxidized coal. This work offers a foundation for stopping coal reignition from happening.</p>