The invention relates to a fire-extinguishing composition taking a porous adsorption material as a carrier. The fire-extinguishing composition contains a metal salt and an organic non-metal compound, wherein the metal salt is adsorbed by the adsorption material with a micron-grade or nano-grade pore diameter. The mass ratio of the metal salt to the organic non-metal compound is 1: (0.4-3.6). The fire-extinguishing composition takes pyrotechnic type medicaments as a thermal source and a power source; and high temperature formed by combusting the pyrotechnic type medicaments is utilized to enable the pyrotechnic type medicaments to be heated and decomposed to release fire-extinguishing substances or drive the porous adsorption material loaded with the solid or liquid metal salt to be released and extinguish the fire. The fire-extinguishing composition disclosed by the invention takes the porous adsorption material as the carrier and the pore diameter can reach from the micro grade to the nano-grade; and the adsorption material with the pore diameter can disperse the solid or liquid metal salt which has the fire-extinguishing effect into the carrier in the micron-grade or nano-grade form, so that the fire-extinguishing efficiency is greatly improved.