Abstract:Through the medium of the acoustic emission test for the failure process of rock in the state of stress, the characteristics of acoustic emission in the whole process of rock failure was researched, including the relation of acoustic emission with time/stress level. It was shown that the rate of acoustic emission event at different rock stress level changed greatly; At the time when the rock strength approached to the peak value, the increasing velocity of stress in unit time reduced and the rate of acoustic emission event decreased obviously.