Abstract: In order to study the effects of iron tailings powder on the mechanical performance of alkali-activated slag foam concrete, alkali-activated slag concrete doped with powdered iron ore tailings was made into 100mm×100mm×100mm cube specimens, which was respectively cured 3 days, 7 days and 28 days. Then the compressive strength of concrete block was tested. The results show that with the increase of the apparent density of alkali-active slag foam concrete, compressive strength also continually grows. When the content of iron tailings powder rises from 10% to 30%, the compressive strength of the alkali-active slag foam concrete increases too. When the content of iron tailings powder rises from 30% to 50%, the compressive strength decreases, and the loss of strength is obvious. With the increase of fineness of iron ore tailings powder, the compressive strength of the alkali-active slag foam concrete gradually improves.