Abstract: To deeply analyze the molecular structural characteristics of Nanlutian coal and promote the efficient development and clean utilization of coal resources, this study employed characterization methods including industrial analysis, elemental analysis, X-ray photoelectron spectroscopy, solid-state nuclear magnetic resonance, etc. The structural parameters of Nanlutian coal were determined, and molecular dynamic calculations were combined to construct the molecular structure models of low-density group enrichment samples (NLTL) and high-density group enrichment samples (NLTH). The constructed molecular structure models were optimized, yielding the lowest energy structures and energy parameters for NLTL and NLTH molecules. Based on the true density of raw coal and the proportion of low-density and high-density groups in the raw coal, an aggregated structure of Nanlutian raw coal (NLTC) was constructed. The results indicate that Nanlutian coal has a high oxygen content and a low sulfur content. Oxygen elements mainly exist in the forms of carboxyl, phenol hydroxyl, and ether, with a ratio of approximately 1∶1∶1. Nitrogen elements in NLTL mainly exist in the form of pyrrole, while in NLTH, they mainly exist in the form of pyridine. Aromatic carbons in NLTL and NLTH structures constitute the main body of the carbon framework, accounting for 61.32% and 57.06%, respectively. The proportions of aliphatic carbons are 25.15% and 28.99%, respectively, with X_BP values of 0.140 and 0.221. The main aromatic structures in NLTL are benzene and naphthalene, while in NLTH, the main aromatic structure should be naphthalene. The total number of aromatic carbon atoms is 81 and 78, respectively, with molecular formulas of C₁₃₂H₁₀₉N₃O₂₈ and C₁₃₆H₁₁₇N₃O₂₅ and molecular weights of 2185.32 and 2193.43. After model optimization, the total potential energies of NLTL and NLTH are 2048.05 kJ/mol and 1612.60 kJ/mol, respectively, with NLTH having lower total potential energy, indicating a more stable molecular structure. During the process of simulating the aggregated structure, the lowest energy and stable aggregated structure of NLTC with a density of 1.45 g/cm³ was obtained by geometric optimization and annealing dynamic simulation, with a decrease in total potential energy of 7470.57 kJ/mol, primarily due to the reduction in van der Waals energy, followed by torsional energy, angle energy, electrostatic energy, and inversion energy, consistent with the density of the original coal.