A series of iron-titanium mixedoxides de-NOx catalysts were prepared by replacing the Fe(NO3)3 with FeSO4. Among this series of catalysts, the Fe0.5Fe0.5TiOy catalyst shows the advantages of high stability,water-sulfur tolerance, excellent low-temperature activity and catalytics electivity. The catalysts were characterized by X-ray diffraction(XRD), Raman spectroscopy(Raman), specific surface area test(BET),programmed temperature rise method(H2-TPR, NH3-TPD, O2-TPD), X-ray photoelectron spectroscopy(XPS) and In situ infrared(In situ DRIFTs). The results show that the Fe0.5Fe0.5TiOy catalyst has a larger specific surface area（65.056 7 m2/g）, more surface reducible species,more acid sites and higher surface active oxygen concentration. Additionally, it is determined that the NH3-SCR reaction process on Fe0.5Fe0.5TiOy catalyst mainly follows the E-R mechanism.