Abstract: In order to prevent and control hydrogen sulfide gas in coal mine, we establish H₂S decomposition simulation experiment system, and use ozone ultraviolet light decomposition technique to carry out the decomposition of hydrogen sulfide. These factors including the number of light sets, ozone, wind speed affecting the decomposition rate of H₂S were studied. The experimental results show that the degradation rate of H₂S decreases with the increase of the inlet concentration of H₂S, and increases with the increase of ozone treatment time, and decreases with the increase of wind speed.