Abstract: Bacterial desulfurization and column leaching were used to decrease the content of sulfur in sulfide ores' surface to a extreme low level even below the critical value so that the spontaneous combustion tendency of the desulfurized ores weakened.The experiment results show that the maximal desulfurization rate can reach 61.82% after 44 d treatment,and gradually increases with prolonging time.Based on the analysis of the spontaneous combustion tendency of sulfide ores,it is indicated that the oxidation weight gain rate of sulfide ores in 5 d decreases from 2.044% to 0.902% while the ores' spontaneous combustion point increases from 209.6℃ to 319.8℃.As a result,the spontaneous combustion tendency downgrades from level Ⅰ to level Ⅲ and the risk of spontaneous combustion is lowered.