Molecular simulation can explore the molecular structure characteristics of coal from thmolecular level, which is of great significance for the further processing and utilization of coal and efficient transformation. Huolinhe low-rank coal (HLH) sample was selected as the research object, and the structural parameter information of Huolinhe low-rank coal was obtained by industrial analysis element analysis, FTIR and 13C solid nuclear magnetic resonance spectroscopy. The results show that the bridge cycle ratio of HLH coal is 0.258, the aromaticity is 39.61%, and the number of aromatic ring substituents is mainly 4. The aromatic structure is mainly benzene, naphthalene and phenanthrene, and the fatty carbon structure is mainly ring. The molecular formula of coal is C194H150O40N2 and the molecular weight is 3 149.25. In the macromolecular structure of coal, the aromatic structural units include 1 benzene ring, 2 naphthalene and 3 phenanthrene. Nitrogen atoms include 1 pyridine and 1 pyrrole. Through simulation software, the molecular structure model of coal is constructed and optimized. After optimization, the energy of the model was significantly reduced and the structure was more stable.