Abstract: In order to study the oxidation characteristics of the by-product carbonized powder in the production process of coal activated carbon, the raw coal and carbonized powder used in production were collected, and by scanning electron microscope experiment, nitrogen adsorption experiment, thermogravimetric experiment, Fourier transform infrared spectrum experiment and nonlinear thermodynamics method, the pore size structure, characteristic temperature, active functional group and apparent activation energy of the samples were analyzed and calculated. The results show that the pore structure and specific surface area of carbonized powder are more developed than that of raw coal; at the same heating rate, the temperature at the ignition point and the temperature at the maximum oxidation rate of carbonized powder are lower than that of raw coal; compared with the raw coal, the content of aliphatic hydrocarbon, some oxygen-containing functional groups and aromatic hydrocarbon in carbonized powder decrease, while the content of hydroxyl increase; the apparent activation energy of carbonized powder is lower than the raw coal. The comprehensive analysis shows that the carbonization process can lead to the improvement of the oxidation spontaneous combustion of carbonized powder, the research results can provide theoretical basis for the prevention and comprehensive utilization of the spontaneous combustion of carbonized powder.