The invention provides a fireproof and corrosion-prevention composite material for a steel structure. The fireproof and corrosion-prevention composite material sequentially comprises a first fiber reinforced concrete layer, a first fiber reinforcement layer, a first fireproof fiber layer, a first fluroresin layer, a second fluroresin layer, a second fireproof fiber layer, a third fireproof fiber layer, a second fiber reinforcement layer and a fourth fluroresin layer from inside to outside, wherein the first fluroresin layer, the second fluroresin layer and the fourth fluroresin layer are dopedwith fireproof grains; the second fiber reinforcement layer is doped with activated carbon grains and nano silicon dioxide grains; the third fireproof fiber layer is doped with the activated carbon grains and the nano silicon dioxide grains. According to the fireproof and corrosion-prevention composite material for the steel structure, the fiber reinforcement layers, a corrosion-prevention layerand fireproof layers are arranged so that the composite material has high mechanical properties and also has fireproof and corrosion-prevention properties. According to the fireproof and corrosion-prevention composite material, the fireproof grains are added into the corrosion-prevention layer so that the fireproof performance of the corrosion-prevention layer is improved. The activated carbon grains are added into the fireproof layers and the reinforcement layers so that the composite material can adsorb toxic gas generated by ablation of the corrosion-prevention layer.