It is essential to forecast water inrush area by processing the rich amount of information for hydrogeology in the mine. In this paper, we commence the study from the controlling factors of water inrush. Then we study the fitting process between AHP (Analytic Hierarchy Process) model and GIS normalization information after determining the controlling factors of water inrush level. Finally, we establish a water damage forecast model of coal footwall in mine. This paper experiment this method to carry out risk assessment of testing mine area, and verify it is validity to forecast water inrush.