Abstract: The 915MHz microwave irradiation experiment was carried out in Shanxi Huozhou coal. The FTIR analysis of the surface coal sample and the bottom coal sample after microwave irradiation was carried out, and the comparison with the original coal sample was carried out to study the effect of microwave radiation on the carbon structure in coal. The results show that the aromatic structure of Huozhou coal mainly exists in the form of disubstituted or tetrasubstituted benzene rings, which account for 73.58% of the aromatic structure. It can be seen that the degree of condensation of coal is low. The aliphatic structure mainly exists in the structure of -CH3 and methylene-CH2, wherein the proportion of -CH2 in the total fat structure content reaches 77.43%. Therefore, there are more alkyl side chains in the raw coal sample. After 915MHz microwave irradiation, the content of benzene ring monosubstituted and benzene ring pentasubstituted in the aromatic structure decreased, and the content of benzene ring disubstituted and tetrasubstituted compounds increased. Microwave radiation has an effect on the coal sample structure. Compared with the preirradiation coal sample, the relative content of the methylene (-CH2) symmetry and asymmetric stretching vibration in the aliphatic structure increased by 3.77% and 10.75%, the relative contents of CH stretching vibration and CH3 asymmetric stretching vibration decreased by 3.26%, 5.68%, and 0.51%, and 1.81%, respectively.