A new method for extinguishing fire is provided, characterized in that a pyrotechnic agent is used as a heat source (energy) and a power source (driving gas); during use, the pyrotechnic agent is ignited, and the high temperature generated by the combustion of the pyrotechnic agent is utilized to make a fire extinguishing composition produce a large amount of fire extinguishing substance, which is sprayed out together with the pyrotechnic agent, so as to achieve the purpose of extinguishing a fire. As compared with conventional aerosol fire extinguishing systems, gas fire extinguishing systems and water-based fire extinguishing systems, the fire extinguishing method of the present invention is more efficient and safer.