Abstract: In order to study the bearing characteristics and reasonable width of the filling body beside the gob-side entry retaining in inclined coal seam, taking the gob-side entry retaining in the left seventh working face of Xintie Coal Mine in Heilongjiang Province as the background, the theoretical analysis method was used to analyze the dynamic impact and static pressure of gangue, and the influencing factors of dynamic impact and static pressure were clarified. The numerical simulation software was used to analyze the stress distribution and deformation characteristics of the surrounding rock of the gob-side entry retaining under the width effect of the filling body, reveal the bearing characteristics of the filling body and determine the reasonable width of the filling body. Finally, the engineering application was carried out. The results show that the dynamic impact of gangue on roadside filling body increases with the increase of gangue quality, mining height and coal seam dip angle, and decreases with the increase of collision time and slip length. The static pressure effect of gangue on roadside filling body increases with the increase of gangue bulk density, coal seam dip angle, mining height and working face length. The minimum width of the roadside filling body is calculated to be 1.36 m by the theory. With the increase of the width of the filling body, the bearing capacity and deformation resistance of the filling body gradually increase, and the 'elliptical elastic core ' which is biased towards the goaf is formed inside the filling body. Finally, the width of the roadside filling body is determined to be 2m. The engineering application shows that the deformation of surrounding rock of gob-side entry retaining is small by using the parameters of roadside filling body, which meets the needs of daily production.