Abstract: Caving of irregular caving surrounding rock under complex conditions is always the difficulties in the research field of caving of fractured rock mass.The more complex the conditions such as lithology,fault,joint,cavity morphology and surrounding goaf,the more difficult it is to characterize the caving characteristics of surrounding rocks in the goaf.During the mining of the M2 orebody in Shirengou Iron Mine,the lower civilian goaf suddenly penetrated to the -210 m level,forming the M2 main goaf with large buried depth,large scale,irregularity and located in the main production.Meanwhile,four concealed empty areas induced by illegal mining are distributed in the north of the M2 main goaf,which seriously threatens the safety of mine production.Therefore,a method combined 3D detection,3D modeling and 3D numerical simulation is proposed to predict the caving range of surrounding rock in the irregular goaf.Threedimensional laser scanning technology is used to detect the morphology and location distribution of the goaf.Then,a 3D numerical model with the complex formation conditions and the maximum irregular section of the goaf is established by the Rhino.The 3DEC is used to study the spatial and temporal evolution characteristics of surrounding rock of M2 main goaf under the influence of mining stress formed by surrounding goaf excavation,and the maximum caving range of surrounding rock is obtained.Moreover,the sum of the horizontal crosssectional radius of the goaf and the maximum horizontal caving range is identified as the radius of the safety isolation zone,which can ensure the safety management of the goaf and the safe production of surrounding orebodies.The results show that while the surrounding rock caving activity in the M2 main goaf is expanding upward,it is also developing along the direction of the orebody strike,and the range of surrounding rock caving on the north side is much larger than that on the south side.In addition,the existing mining roadway and the medium and deep hole perforation project can be effectively used by mining the orebody on the south side of the safety isolation zone,so that the production capacity of the mine can be effectively connected.