Special steel tailing foam concrete was prepared from special steel tailing powder. Special steel tailing powder and products in different curing stages of special steel tailing foam concrete were measured by Fourier transform infrared spectroscopy(FTIR). Related performances of special steel tailing foam concrete(curing age is 28d) were tested. The results show that the 3CaO·SiO2 reacts with special steel tailing foam concrete at the early stage of the curing process(07d); 2CaO·SiO2 reacts with water absorbted in special steel tailing foam concrete, generating C S H gel and Ca(OH)2 at the late stage of the curing process(1428d). Special steel tailing foam concrete(curing age is 28d) has good light weight performance and good mechanical performance, at the same time, the safety of special steel tailings powder application is greatly improved. Its dry density is 62769g/cm3, compressive strength is 2671MPa, internal exposure index IRa and external exposure index Iγ are 01.