In this work, a magnetic WO3/Fe3O4 catalyst was synthesized by grinding-calcination method and applied in the deep oxidative desulfurization of dibenzothiophene (DBT). The results showed that the as-synthesized WO3/Fe3O4 had high catalytic efficiency for sulfur-removal. The content of WO3, amount of the catalyst, TBHP/DBT molar ratio and reaction temperature had significant effects on the desulfurization efficiency. The highest DBT conversion of 92.3% was achieved on 35% WO3/Fe3O4 catalyst with the O/S ratio of 12:1 at 100 °C for 4.5 h. The results of this study revealed that WO3/Fe3O4 catalyst has excellent potential for desulfurization properties because of its high catalytic activity and easy separation ability under an external magnetic field.