Abstract:Goaf is one of the significant source of risk in metal mine. The stability of goaf is one of the key factors which ensure the normal production of mining enterprises. Since Xiadian gold mine started minging ore by non-pillar sublevel caving method at -363m level in August 20, 2003, it has been 10 years and Xiadian gold mine has been mining to -692m level in which it is significant to analyze the stability of hidden goaf generated by caving method. This article establishes an ore body model of caving method by a software called Surpac and predicts the falling height of goaf, then gets a result that the position which has highest falling height is -251m. Afterwards, this article simulates the excavating process by FLAC3D according to the mining order which divides the excavation into 12 times, then analyzes stress, displacement and wreck of the plastic area and gets the conclusion that deformation takes the goal’s upper part as center, extending in the form of a circle, and the maximum deformation is at the center of goaf where settlement is 18cm. In addition, the boundary of goaf has the minimum settlement which is 4cm. In conclusion, surface settlement displacement was not large and goaf collapsion would not extend to the surface.