The invention relates to the field of coal mine safety technique, specifically to a down-hole coal and gas outburst hazard early warning system and early warning method. The coal and gas outburst synthesized early-warning system, uses the existing local area network to connect a synthesized early-warning data server, an early-warning data management system and the existing coal mine safety monitoring system; analyzes the coal and gas outburst early-warning data in the synthesized early-warning data server by an outburst early-warning module; and emits early-warning information based on the analyzed result. The inventive coal and gas outburst synthesized early warning system and early warning method can perform centralized management and comprehensive analysis of the geological structure, coal seam occurrence, gas occurrence, mining production, daily forecast indicators, outburst forecast, gas emission and other security information that originally scatter in various functional sections of coal mine on the geographical information system GIS platform, integrates the existing resources, improves the accuracy of early warning, so that the early warning is both real-time and forward-looking, and can effectively prevent the occurrence of coal and gas outburst in coal mine.