Abstract: In view of high sulphur coal acidification in Wuhushan coal preparation plant before mineral processing.The genetic mechanism of coal sample acidification is studied by using experiments and microbial classification sequencing technology.And the relative abundance of microorganisms at different classification levels is also calculated.The results show that the microbial richness is highest in raw coal just extracted from the mine.In addition, there are also four thiobacillus species with sulfur oxidation function, namely Acidithiobacillus, Sulfobacillus, Acidiferrobacter and Azonexus, and the microbial content gradually decreases with the increase of external time.Finally, based on the theory of microbial recombination, the mechanism of this genus is analyzed.The main reason of coal sample acidification is that the pyrite in the high-sulfur coal formed the solution of sulfuric acid and ferric acid under the combined action of air, water and microorganisms.Thus, it affects the processing and utilization of coal.