Abstract: For the situations of serious wall spalling and poor stability of coal wall in full-seam mining fully-mechanized working face above 6.5 m thick coal seam in Wangzhuang Coal Mine, combined with the test results in field, the instability mechanism of coal wall spalling is analyzed. Based on the fact that the higher mining height easily leads to the serious wall spalling, we propose a method to control the spalling by using “stepped coal wall”, and analyze its mechanism. The result shows that the failure surface shape of working face of coal wall spalling is similar to the conical surface, and its scale is similar to the “wedge”; the coal wall is divided into several front and back staggered steps from top to bottom. After that, the coal wall stress can be improved, which is conductive to the coal wall spalling control.