Abstract: The iron ore tailing (IOT) and river sand are respectively soaked into three kinds of alkaline solution with different pH to test the mass loss of granules, pH and electricity conductivity of soaking solution in different periods. The results show that IOT is not susceptible to alkali-silica reaction. Mass loss of river sand is higher than that of IOT under the alkaline solution. The pH of soaking solution with river sand has more significant decrease compared with that of IOT, whereas inversely variation for electricity conductivity occur following prolongation of time. Better chemical stability of IOT is proven than that of river sand, which provides a reliable guarantee for application of IOT in Portland cement materials substituting river sand as fine aggregate.