In order to achieve quick response and scientific decision-making, it is necessary to build a distributed emergency decision-making system. In this paper, the system uses a frame structure with combination of B/S and C/S technologies, and bases on WebGIS and other technologies, which provide a technology platform for the system. This system has the ability to report the disaster situation to the command center, simultaneously, it also fast implements auxiliary decision. This article focuses on the design thoughts, key technologies, and applications, and finally an example is given for analysis and simulation to explore the system specific application in an emergency.