The invention discloses a mould-proof aerated building block and a making method thereof. The mould-proof aerated building block is made from, by weight, 17-29 parts of silicon micro-powder, 22-36 parts of fluorite slag, 9-16 parts of crab shell powder, 12-18 parts of sulfur slag, 5-10 parts of nanometer silver supported zirconium phosphate, 4-7 parts of polyacrylamide, 5-10 parts of traditional Chinese medicinal residue ash, 13-21 parts of slag micro-powder, 14-22 parts of porous ceramsite, 15-25 parts of white cement, 11-17 parts of calcined loess, 10-15 parts of quicklime, 1-2 parts of hydrogen peroxide and a proper amount of water. The crab shell powder, the sulfur slag, the nanometer silver supported zirconium phosphate, polyacrylamide, the traditional Chinese medicinal residue ash and other raw materials added in the invention can obviously improve the mould proofing performance of the aerated building block and have no influences on the physical-mechanical performances of the aerated building block. The aerated building block made in the invention has excellent mould proofing performance, has a bacteriostasis rate reaching 99.5% or above, and also has excellent impact, thermal ageing and corrosion resistance.