The invention provides a method for producing an air entrapping building block by utilizing ardealite, comprising the following processing steps: mixing materials according to the following mass ratio: 50-70 percent of ardealite, 10-15 percent of cement, 15-25 percent of yellow phosphorus slag and 5-10 percent of lime, then adding water according to 85-100 percent of the mass of the mixture, adding aluminium powder according to 0.04-0.06 percent of the mass of the mixture and adding an auxiliary agent according to 0.5-0.8 percent of the mass of the mixture, and then mixing to prepare a sizingagent; and finally obtaining the air entrapping building block through foaming, standing and steam curing. The air entrapping building block has the advantages of stable physical properties, light weight, good heat-insulation property, high waste use ratio, simple process, low cost, environmental protection, natural resource saving and the like, and can be used as non-load bearing partitions of urban high-rise buildings and as heat-insulation building blocks of low-temperature warehouses, heat-insulation warehouses and cold storage warehouses of industrial equipment.