Abstract: The occurrence characteristics of major elements in coal are an important way to understand the structure and reactivity of coal. Among them, the occurrence characteristics of carbon, oxygen, nitrogen and sulfur in coal are important contents in the study of coal structure. Through X-ray photoelectron spectroscopy （XPS） analysis, scanning electron microscope （SEM） examination, and X-ray diffraction （XRD） analysis of coal samples from Dongqu Coal Mine and Yachen Coal Mine similar coal grades, this paper has unveiled the microscopic morphological features of these two coals, the types of minerals they contain, as well as the reasons for the differences in the occurrence characteristics of carbon, oxygen, nitrogen and sulfur elements at the molecular level between the two types of coal. The research results show that there are adherent mineral particles on the surface of both Dongqu Coal and Yachen Coal, and the surface morphology of the particles is similar for both of them. In both coals, carbon is present in four forms, C—C, C—O, C=O and COO—. Of these, C—C is the predominant form of carbon, and both coals contain low levels of C=O and COO—. Compared to Yachen Coal, Dongqu Coal has a higher C—H content and a lower C—O content. Oxygen element is present in three forms: COO—, C—O and C=O. The analysis revealed that Dongqu Coal with lower COO— and higher C—O content has higher pyrolysis efficiency than Yachen Coal. In addition, nitrogen is present in four forms: pyrrole nitrogen （N-5）, pyridine nitrogen （N-6）, protonated pyridine （N-Q） and nitrogen oxide （N-X）. Compared to Yachen Coal, Dongqu Coal has a higher nitrogen oxide content. Dongqu Coal can be denitrified using selective catalytic reduction （SCR）. In contrast, Yachen Coal contains mainly pyridine nitrogen, pyrrole nitrogen and protonated pyridine. Considering the very low levels of nitrogen oxides, denitrification can be carried out using activated carbon adsorption and catalytic combustion methods, among others. Sulfur element is present in six forms: thioether（thiol）, thiophene sulfur, sulfoxide sulfur, sulfone sulfur, sulfate sulfur, and pyrite sulfur. The sulfur structure of both Dongqu and Yachen Coals is dominated by organic sulfur and supplemented by inorganic sulfur, with thiophene sulfur, sulfoxide sulfur and sulfone sulfur both accounting for around 80% of the sulfur content of their respective coals. The inorganic sulfur in both coals is dominated by sulfate sulfur. The focus of desulfurization can be on inorganic sulfur （sulfate sulfur） as the thioether （thiol） content is small and the thiophene sulfur, sulfoxide sulfur and sulfone sulfur are structurally stable and cannot be easily removed. Post-combustion flue gas desulfurization and wet desulfurization can be used for desulfurization at Dongqu and Yachen Coal Mines. This study is of great significance for the fine processing and utilization of coal, reducing environmental pollution, promoting the recycling and environmental protection development of coal, and expanding the use of coal.