Abstract: Aiming at the stability of large cross-section of filling body in cemented filling, numerical simulation was applied to study the law of transmutation in filling body.The arrangement of reinforcing steel bar in filling body can be effective in reducing the area of tensile stress and improve the stability of the stope roof.The limesand ratio of 1:4 precursors of the filling body can be used as bearing layer.And the deformation and the law of Stress distribution of filling body are in accordance with bearer beam.The filling body can replace the reinforced concrete artificial bottom.