The existing Mined-out area may induce impact ground pressure hazard in some mine.For evaluating the stability of the mined-out area,the forming process of the mined-out area was simulation with 3d-ANSYS software,and the analyzed results were checked according to the advanced theory of ore pillar strength.The result showed that the mined-out area can not induce impact ground pressure hazard,but partial caving may occur.