To provide a fire extinguishing system which enables quick, effective and efficient fire extinguishing only to a fire starting site by identifying the site when fires break out within various constructions such as buildings and tunnels.

The fire extinguishing system includes a rail suspended from the ceiling of the construction, at least one self-travelling fire extinguishing robot running on the rail, a standby station so arranged as to house the self- travelling fire extinguishing robot, and a plurality of fire detectors installed within the construction. When the outbreak of fires is detected with the fire detector, the self-travelling fire extinguishing robot is moved to any fire starting site from the standby station to get the fire extinguishing agent jetted out of a fire extinguishing agent jet nozzle provided on the self-travelling fire extinguishing robot to the fire starting specified with an infrared camera.