Abstract: In order to improve the coal mining rate of the III4303 large mining height working face, the coal mining technology without coal pillars is used to study the coal mining technology without large coal mining face through the combination of laboratory tests, theoretical analysis and industrial tests. According to the test results of the mechanical properties of the soft-molded concrete, the strength of the soft-molded concrete is higher than that of the ordinary concrete. The compressive strength is 38.3 MPa when the standard is maintained for 28 days. Combined with the specific conditions of the working face of the III4303 large mining height, it is determined that the anchor net is used in the lane. Combined support of cable + corrugated steel strip, the width of C30 flexible mold concrete is 1.5m, and the theoretical analysis is used to verify the bearing capacity of the roadside filling body. The engineering practice shows that after the implementation of the non-coal mining technology, the maximum displacement of the top and bottom plates and the two gangs of the return air duct of the III4305 working face are 220mm and 240mm respectively, which ensures the stability of the surrounding rock of the roadway; It is 102 million yuan, which has improved the production efficiency of the mine.