Abstract: In response to the shortcomings of the large inclination angle of the underground working face and the difficulty of roadway layout during extremely close distance coal seam mining in A certain mine, as well as the low efficiency of top coal caving comprehensive mining, a horizontal segmented step-by-step top coal caving rapid comprehensive mining technology is proposed. The joint mining of two coal seams with high inclination angles and extremely close distances is carried out, and a connecting roadway with an inclination angle of 30°is set up between the coal seams. This not only reduces the amount of underground excavation work but also forms a "U" - shaped ventilation structure, improving the ventilation safety of the working face. According to the practical application in coal mines, the horizontal segmented step-by-step top coal caving rapid comprehensive mining technology can not only effectively improve the working environment during coal seam mining at high dip angles and extremely close distances, but also reduce the labor intensity of operators. The top coal extraction rate is increased from 70% to over 86%, and the efficiency of top coal comprehensive mining operation is increased by 8.4%. The annual production capacity of the working face reaches 397200 t/a, forming a suitable for underground large dip angles The rapid comprehensive mining operation system for extremely close coal seams effectively improves the efficiency and safety of comprehensive mining operations under complex geological conditions underground.