Abstract: Through uniaxial compression acoustic emission experiments to goaf surrounding rock sample of a Mine, acoustic emission parameter values such as energy rate and event rate were obtained when rock failure. According to these values, parameters of acoustic emission monitoring system were set. Through statistics for long-term operation result of the acoustic emission monitoring system, waveforms of various underground activities namely rock acoustic emission, drilling, blasting, artificial crushing of large ore, ore drawing and percussion and parameter range of all kinds of the waveforms were summarized. Instability criterion of the goaf with characteristics of the energy rate and event rate were determined, so as to provide a reliable basis for judgment of underground pressure disaster.