In order to identify an accessible substance that efficiently prevents low temperature oxidation of coal which can lead to coal spontaneous combustion, this work investigated the use of sodium humate (SH) as a possible inhibitor of coal oxidation. Three coal samples (CJS, BZ and PING) were treated with sodium humate, oxidation of the coal during room temperature to 600 degrees C showed that the addition of sodium humate increases the initial exothermal temperatures (about 5-10 degrees C) and lower heat released (1692-2858 J/g) significantly. A distributed activation energy analysis showed that the presence of SH increased the activation energy barrier throughout the entire oxidation process, and the maximal incrasement enhanced by 29 kJ/mol. Combining these results with in situ FTIR analyses of functional groups on coal samples with and without SH, a mechanism for coal oxidation in the presence of SH is proposed. In this model, the addition of SH to the coal promotes the formation of hydrogen bonds and stabilizes ether groups, thus slowing the oxidation process. The results of this work suggest that SH is an effective inhibitor of coal oxidation.