In some methods usually used in goaf stability monitoring, some shortages (only monitoring point area, need manual installation, poor real-time performance, etc) occur. 3D laser scanning is used to obtain goaf space profile, then to analyze goaf stability. The realization of high precision control of 3D laser scanner is focused on by means of mechanical optimization, attitude compensation, adaptive control and other technical means. The method greatly improves performance of 3D laser scanning system used in goaf monitoring, meets the needs of practical application of mine, meantime, it can provide references for road and bridge monitoring and cultural relic protection.