Abstract: Roof water disaster was the most serious threat to mining activities in Cuimu Mine, and it had multiple features which made it hard to predict and control. In order to ensure the safety of mine production, through the statistical analysis of a large number of field measured data, the response time of aquifer water level was adopted, and combined with the location of water inrush, instantaneous water quantity, water change rate and water inrush quality characteristics and other discriminating parameters, the roof water inrush was divided into two categories: static reserve release and separation layer water inrush. It is found that the roof water damage in Cuimu Coal Mine is mainly caused by water inrush from separate layers, and the roof water inrush can be predicted preliminarily by discriminant parameters.