Abstract: In order to analyze the influencing factors of H₂S extraction and absorption in steep-inclined and extremely thick coal seam, two tests that the influence of drainage negative pressure on drainage radius and drainage volume and influence factors analysis of water injection rate and wetted radius were designed. The tests show that drainage radius increases logarithmically with the increasedof drainage negative pressure, and drainage concentration decreases exponentially with the increase of discharge time; water injection rate is negatively correlated with water injection pressure, and the addition of H₂S absorption liquid has little effect on water injection time and water injection volume, but has little effect on wetting radius; adding wetting agent will increase the amount of water injection, and wetting radius. The wetting radius of coal is negatively correlated with the water injection pressure, and the wetting radius of the test hole below the water injection hole is obviously larger than that of the horizontal detection hole as a whole.