Abstract: To elucidate the regulatory mechanism of water with different salinities on the spontaneous combustion and oxidation behavior of coal, fresh raw coal samples were collected from Xiaobaodang Coal Mine in Shaanxi, and immersion treatments using distilled water and saline solutions with salinities of 1 000 mg / L and 10 000 mg / L were designed. Temperatureprogrammed oxidation experiments, scanning electron microscopy (SEM), and Materials Studio molecular dynamics (MD) simulations were employed to systematically investigate the macroscopic oxidation characteristics, microscopic structural evolution, and oxygen adsorption behavior. The results show that increasing salinity significantly suppresses the oxygen consumption rate of coal samples,particularly in the temperature range of 120-180 ℃. High-salinity water reduces the peak oxygen consumption rate through the combined effects of pore blockage and active-site coverage,with the peak value decreasing by approximately 46% compared with that of the distilled water group. SEM observations reveal the formation of dissolution pits and flocculent aggregates on the coal surface,indicating that mineral ions modify the pore structure and occupy strong active sites through dissolution and ion exchange. Molecular dynamics simulations reveal that the water film formed by mineral ions enhances oxygen adsorption but reduces the adsorption heat to approximately 1. 5 kcal / mol,resulting in weak physical adsorption that is insufficient to initiate oxidation reactions. This study elucidates the inhibitory mechanism of saline water on coal spontaneous combustion,providing a theoretical foundation for the precise prevention and control of coal spontaneous combustion in highsalinity mine water environments.