Abstract: For improving digital management and assisting decision-making of water disaster prevention and control in coal mines, the design principle of system for prevention and control of water hazards in coal mines was proposed from the point of management and decision-making. The system information flowchart was analyzed. The database and function modules were designed. The key technologies and their realization in the system were analyzed, i.e., discrimination of water-inrush source, risk evaluation of water hazards in coal seam floor and roof. The C/S part of the system was developed on the basis of GIS components, which can conduct well map management, information extraction and model computation, and the map and data can be distributed in internet with B/S mode.