Abstract: Based on the engineering geological conditions of the hard roof of the medium thick coal seam in Dadougou Coal Mine, in order to implement the non-pillar mining technology of roof cutting and pressure release, the key parameters of roof cutting and roadway retaining are studied and optimized. By combining theoretical analysis with numerical simulation, the influence of cutting roof height and cutting angle on the stress distribution and displacement of surrounding rock along gob side entry is analyzed. In view of the key position of surrounding rock deformation in the roadway non-pillar mining technology, the design parameters of reinforced anchor cable support were designed reasonably. The results show that the reasonable cutting height is 9 m and the reasonable cutting angle is 15 °. The non-pillar mining technology of roof cutting and pressure release is implemented in the field, and the working resistance of the hydraulic support in the working face is monitored. The results show that the effect of gangue retaining and roadway retaining is good, and the effect of pressure relief is obvious.