Abstract: The stability of the roof above the filling body is a key factor affecting the effect of gob-side entry retaining. In view of the problem of roof separation control of gob-side entry retaining at 22301 working face with large mining height in Tunlan Coal Mine, by analyzing the stress characteristics and roof separation mechanism of each stage during the roadway retaining, the mechanical model of roof separation above the filling body was established, the partition dynamic reinforcement control technology of the straight roof above the gob-side entry retaining filling body in thick coal seam was proposed, that is “anchor cable”+ “high pre-stressed anchor cable”+ “high resistance hydraulic prop” stage support for the entry retaining. The field test results show that the maximum subsidence of the roof is 140 mm, and the floor heave is 660 mm. Outside the 150 m behind the working face, the cumulative separation of 0 m to 6 m is 16 mm, and the cumulative separation of 0 m to 2.5 m is 14 mm. The surrounding rock deformation is dominated by floor heave. The overall stability of the roof supported by sub-regional dynamic support reinforcement technology is significantly improved.