Abstract: In order to improve pridiction accuracy of water irruption quantity of mine,the paper introduced an intelligent monitor of water inrush from coal floor based on acoustic emission characteristic according to spectrums of acoustic emission have difference under diffirent stress speeds and fracture of coal-rock with different water content.It gave judgment model of water inrush hazard,introduced design of hardware and software of the monitor in details,and made experiment test for the monitor.The test result showed that the monitor can provide reference for real-time pridiction of undreground water inrush.