The invention discloses a manufacturing method of aerated concrete, which comprises the following steps of: preparing liquid feed liquid; precuring; mixing an amorphous silicon material and water to prepare amorphous silicon material slurry; then mixing the amorphous silicon material slurry, the liquid feed liquid, a crystalline silicon material, one of calcined lime or calcium hydroxide or lime milk, dihydrate gypsum or semi-hydrated gypsum, ordinary portland cement, feldspar materials, strength intensifier, calcined lime digestion regulator, bubble regulator, lubrication tackifier, water repellent, a foaming agent and water; stirring the mixture at the speed of between 800 and 1,500rpm for 3 to 7 minutes to prepare foam slurry; and performing standing curing and still kettle curing to prepare the aerated concrete. The product obtained by the manufacturing method has the characteristics of light weight, high strength, flame retardance, heat preservation, heat insulation, hydrophobic property, long service life, impact resistance, small shrinkage, and the like; moreover, the material sources are wide, and the products are simple and convenient to process and manufacture.