Abstract: This paper studies the stability analysis of -400 m level insulating pillar of deep excavation of l^# orebody of Anqing Copper Mine with FLAC^3D.The results verify that the strain effect diminishes and bump vertical displacement deformation changes in the insulating pillar for the unloading of upper ore -body mining. Due to disturbance of large and thick in-depth mining, stress concentration and parts of the plastic deformation are formed. Tension arch and downward displacement deformation change in the insulating pillar. The displacement deformation approximates conventional displacement deformation monitoring results of the insulating pillar. The overall stability of the insulating pillar in deep mining is good.