Abstract: In order to study the damage characteristics and movement of inclined strata in the steep seam fully mecha- nized mining with sublevel filling along the strike,the mechanical model of inclined strata beam has been built,and the deflection equation of inclined strata beam has been derived. Based on the deflection equation,the maximum deflection positions in the filled area and unfilled area have been work out. Field simulation experiment has been done with the prototype of Xiangyong Coal Mine geological conditions,the result shows that ① by the support effect of filling,the in- clined strata subsidence in filled area is smaller,and the inclined strata subsidence in unfilled area is larger,where the strata is caved. The caved rock fill the GOB bottom and support the lower roof and floor. ② the results of the experi- ment about the unfilled area show that the upper part of inclined strata is tensile failure;the middle part failure form is inclined voussoir beam,the fracture position is above the middle of working face;and the lower part failure form is pul- ling damage,the failure shape is “F”. The secondary balance structure is formed of the lower fractured support area, the middle subsidence area by self-supporting of roof and the upper support area. The field simulation experiment re- sult is conform to the conclusions of theoretical reasoning.