The lightweight thermal insulation wall material（LTIWM） was prepared with iron tailings as the main raw materials, rice husk as the pore forming agent, together with appropriate amount of bentonite and feldspar as the binder and the flux, respectively. The effect of raw materials ratio and firing temperature on the properties of wall material was studied by orthogonal test and single factor test, and the firing mechanism was investigated by thermal analysis instrument（TG DSC）, X ray diffraction（XRD） and scanning electron microscope（SEM）. The results show that the optimal contents of iron tailings, bentonite, rice husk and feldspar are 46%, 35%, 9% and 10%, respectively, and the optimal firing temperature is 900℃. The bulk density, compressive strength, apparent porosity and thermal conductivity of the prepared wall materials under the optimal conditions are 12294g/cm3, 76MPa, 4554% and 02925 W/(m·K), respectively. The firing process can be divided into four stages as dry dehydration, pore formation, bonding and cooling. The main mineral compositions of the materials are quartz, hematite, mullite, microcline, albite and anorthite, the internal crystals are well developed, and the glass phase content and porosity are moderate, which ensure the good performances of the material.