Abstract: Deep rock mass is in the process of mining disturbance, but rock mass is essentially in the loading-unloading process and properties of this process are, in fact, its post-peak strength characteristics. Based on MTS815 rock mechanics test system and PCT - 2 acoustic emission detection analysis system, acoustic emission characteristics of rock for the whole stress-strain and post-peak unloading process under different confining pressure are studied. The results show that AE signal is less before specimens yielding and gradually raise after specimens yield during triaxial compression test. Cumulative acoustic emission ringing-time cure has obvious step, which is the relatively quiet period of AE and indicates that the specimens will failure. When the specimens reach to the stage of residual strength, AE signal is less and the slope of cumulative acoustic emission is decreasing. The AE signal is comparatively less before unloading confining pressure and it becomes more active in the process of unloading confining pressure. The higher the confining pressure, the more the cumulative acoustic emission ring which receives and release more energy. This phenomenon can explain why rock burst is more prone to happen in high geo-stress area.