Abstract: In order to obtain more reliable data on stability analysis of goaf，the 3d laser detector is adopted to detect the mined-out area to accurately acquire its 3D shape and distribution. Combining with the actual model with 3D mining software Surpac for mined-out area，the numerical analysis on the mechanics model is made with FLAC^3D through the coupling technology. Finally，the monitoring results with the on-site photoelastic stress meter and the numerical simulation results are contrasted，and a comprehensive analysis and evaluation on stability of the mined-out area is made. This research can provide a theoretical basis for the subsequent safety production and management.

Key words: Mined-out area, 3D laser detector, Stability, Photoelastic stress meter