Abstract: Magnesium titanate is widely applied as an excellent dielectric ceramic material.In order to improve the purity of magnesium titanate prepared by direct reduction of titanomagnetite, the effect of roasting temperature on purity of magnesium titanate generated from direct reduction roasting of titanomagnetite concentrate producing by low intensity magnetic separation of sea sand iron ore is studied, and the mechanism of its influence is studied by using scanning electron microscopy and EDS spectroscopy.The results show that the manual green pellets with 80% coke are roasted at 1 500 ℃ for 180 min, and a higher purity of magnesium titanate products with a yield of 21.21% and an iron content of 4.35% are obtained by grinding and magnetic separation.The research of influence mechanism indicated that the roasting temperature had a great influence on magnesium titanate produced by direct reduction of titanomagnetite.The content of magnesium ferrite increased firstly and then decreased sharply with the increase of temperature.The elevated temperature is beneficial to promote the magnesium titanate crystal and aggregation of metal iron.When the roasting temperature is raised to 1 500 ℃, the magnesium ferrite formed in the roasted pellet due to insufficient reducing atmosphere can be decomposed, and the metallic iron and magnesium titanate particles are significantly grown and have a clear boundary, which is favorable for the subsequent grinding and magnetic separation, then, a higher purity magnesium titanate can be obtained.