Abstract: This study focuses on the overburden separation grouting problem in 23041 working face of Gaocheng Coal Mine under the special geological conditions of a sliding structural zone. Based on the self-stabilizing balance arch theory, the distribution of key strata in the overburden and the development height of the water-conducting fractured zone were analyzed, and the target grouting horizons were determined to be below key stratum 3, sub-key stratum 4, and the main key stratum. The UDEC numerical simulation software was used to investigate the movement of overburden key strata and the development law of separation spaces beneath them under different thicknesses of the structural zone. The results show that affected by the coal seam dip angle, the maximum subsidence position of the key strata shifts toward the downhill direction of the goaf, and the offset degree increases with the distance from the working face. As the thickness of the sliding structural zone increases, the maximum subsidence value of the key strata tends to decrease: for every 1 m increase in thickness, the maximum subsidence value of each key stratum (sub-key stratum 2, sub-key stratum 3, sub-key stratum 4 and the main key stratum) decreases by approximately 16-32 mm, 23-25 mm, 8-18 mm, and 7-17 mm, respectively. The separation space beneath the target grouting horizon presents an asymmetric “sharp-bottomed bowl shape”, with the separation volume gradually increasing from bottom to top and shifting toward the downhill direction of the goaf at maximum separation angles (sub-key stratum 3, sub-key stratum 4 and the main key stratum) of 4°, 6°, and 6.5°, respectively. For every 1 m increase in structural zone thickness, the maximum separation volume beneath each key stratum (sub-key stratum 3, sub-key stratum 4 and the main key stratum) decreases by approximately 3 mm, 2-4 mm, and 3-5 mm, respectively. Based on simulation results, a “multihorizon and zonal” overburden separation grouting scheme was proposed. Ten grouting boreholes were constructed along the strike of the working face, with the hole bottom at least 140 m above the coal seam roof. The strike length covered by a single grouting zone did not exceed 170 m, and the total grouting volume reached 613 140 t. The maximum surface subsidence value was 308 mm, the average subsidence factor was 0.04, and the subsidence reduction rate reached 60.0%-86.7%. The surface tilt deformation ranged from 0.250 to 1.174 mm/m, and the curvature deformation ranged from 0.002×10⁻³/m to 0.010×10⁻³/m. The surface subsidence and damage reduction effects were significant, and surface structures were effectively protected.