Abstract: The mining and release ratio is a key parameter of the comprehensive mining face in coal mines，which has a significant impact on the degree of crushing of top coal and is directly related to the ef⁃ ficient mining back of the face. Taking 1303 working face of No.3 coal seam in Zhaoxian coal mine as the research object，the supporting pressure in front of the coal wall was analyzed. Combining the field practice and numerical simulation method，the distribution of support pressure，damage range and coal wall stabili⁃ ty state of the top coal under different mining and release ratios were analyzed. The results show that: when the mining and release ratio is less than 1∶3，the peak vertical stresses in the top and bottom plates are 22.5，24 and 26 MPa respectively，and the overrun distance is about 100 m. After the mining and release ratio is more than 1∶3，the peak stresses in the top plate are increased by 2.5 MPa，and the peak stresses in the bottom plate and the inner coal seam are decreased by 1.52 and 2 MPa respectively，and the overrun distance is increased to 120 m. The mining and release ratio is more than 1∶3，and the peak stresses in the top plate and the inner coal seam are decreased by 1.52 and 2 MPa respectively. Under the working condi⁃ tion of mining and release ratio more than 1∶3，the 1303 working face can realize safe and efficient min⁃ ing，but it is necessary to control the upper limit of mining and release ratio to 1∶4.42 to balance the effi⁃ ciency and safety risk.

Key words: mining and release ratio, support pressure, numerical simulation, mining pressure law