Abstract: Simulating the high humidity environment of left coal in the goaf, using of the XK-type temperature-programmed experiment system and TD-2000 true density analyzer for low combustion property of anthracite coal that mixed diffident contents of pyrite, the test determined the oxygen consumption rate, production rule of CO and pore structure of coal on the high humidity environment during the low temperature oxidation process of coal. The experimental results show that the promotion of sulfur to coal spontaneous combustion does not increase with the increasing of coal sulfur content, excess sulfur content has some inhibition for coal spontaneous combustion, and the coal spontaneous combustion achieves peak when the sulfur content is 5%, this provides theoretical basis for the work to preventing and controlling high-sulfur coal seam spontaneous combustion.