Abstract: To effectively solve the technical problems of hydrogen sulfide overrun in steeply inclined thick coal seam top coal caving mining, we comprehensively analyze the hydrogen sulfide emission factors and reasonably and effectively control and reduce the harm of hydrogen sulfide to the human body. This paper studied the effect of cutting rate of coal cutter, intensity of caving coal, coal mining machine cutting the top / bottom coal and tensile slip process on hydrogen sulfide emission concentration, and obtained the laws that hydrogen sulfide emission increases with the increasing of coal cutting speed, caving strength of coal. By taking the treatment means of spraying absorption liquid to absorb hydrogen sulfide, the reduction efficiency of hydrogen sulfide emission reached 84.4% above at working face of the driver, the corner and return airway, and hazard prevention of hydrogen sulfide achieved breakthrough results.