The invention discloses environment-friendly anti-cracking building foam concrete and a method for preparing the same. The environment-friendly anti-cracking building foam concrete comprises, by weight, 85-100 parts of moderate heat silicate cement, 20-30 parts of admixtures, 10-25 parts of stone, 15-35 parts of aluminate cement, 10-15 parts of phosphorus slag, 18-25 parts of phenolic fibers, 10-20 parts of montmorillonite, 20-25 parts of dodecylbenzene sulfonic acid air entraining agents, 10-15 parts of triethanolamine, 10-20 parts of polycarboxylate superplasticizers, 5-10 parts of compositeexpansive agents, 8-15 parts of stabilizers and an appropriate quantity of water. The environment-friendly anti-cracking building foam concrete and the method have the advantages that the moderate heat silicate cement, the admixtures, the stone, the aluminate cement, the phosphorus slag, the phenolic fibers, the montmorillonite, the dodecylbenzene sulfonic acid air entraining agents, the triethanolamine, the polycarboxylate superplasticizers, the composite expansive agents and the stabilizers are effectively matched with one another, accordingly, surface and internal crack due to non-structural reasons such as the temperatures and dry shrinkage of the environment-friendly anti-cracking building foam concrete can be effectively prevented, and the environment-friendly anti-cracking buildingfoam concrete is high in shock resistance and impermeability, applicable to mine operation, good in safety performance and waterproof performance and long in service life.