TiO2 photocatalyst, palygorskite/ TiO2 composite photocatalyst and palygorskite/ magnetic iron oxide/ TiO2 composite photocatalyst were prepared by hydrolyte tetrabutyl titanate and loaded Fe3O4 in the system of ferrous sulfate and potassium nitrate. The composite photocatalyst was studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis diffuse reflectance and magnetic susceptibility (MS). The effects of doped Fe3O4 and doped palygorskite on photocatalysis and a comparative study of the photocatalytic decolorization rate between TiO2 in composite photocatalyst and TiO2 on the market were evaluated by the decolorization of methyl orange. The results indicate that doped Fe3O4 and palygorskite can decrease the average size of anatase in composite photocatalyst and improve the dispersion of anatase. Whether the doped Fe3O4 can improve photocatalytic activity or not is related to calcination temperature of the photocatalyst. Doped palygorskite can affect the best calcination temperature of photocatalyst.