The invention relates to a fire fighting system comprising a databank, an alarm signal transmission module, a fire analysis module, an analysis result output module, a disaster eliminating device control module, a building registering module, a data enquiry module, an alarm signal collecting device, a terminal alarm evacuation device, a disaster elimination actuating device, an isolation device and an automatic power-down device, wherein the devices receive signals of the corresponding modules by a corresponding circuit to control the operation. The fire fighting system integrates multiple functions of alarming fire, evacuating and eliminating fire into a whole, can judge the fire property and the fire danger class in time when fire breaks out, provide a safe evacuation route for personnel in buildings in time, cut off power supplies in a fire scene in time, select optimal extinguishing materials to extinguish fire according to the fire property and simultaneously isolate the fire scene to avoid the extension of the fire.