Abstract: The 0.1Ce/MgAl1.8Fe0.2O4?MgO sulfur-transfer additive was prepared by acid-processed gelatin method. Vanadium trapping capacity of the additive was confirmed through heavy oil micro-reactor evaluation. The comparison of the XRD profile of the V-contaminated FCC catalyst before and after the addition of sulfur-transfer additive proves that the sulfur-transfer additive protect the zeolite in FCC catalyst from being destroyed and can restrain the generation of Mullite at the same time. The DTA results of the mixture of V2O5 and sulfur-transfer show that it is the components in sulfur-transfer additive such as MgO and CeO2 that form the stable new compounds such as Mg3(VO4) and Ce(VO4), which protect the FCC catalyst zeolite from damage. The influence of V2O5 content on DeSOx activity and the crystalline structure was also studied. It is found that the DeSOx activity and renewable performance remains stable and the crystalline phases intact when the content of V2O5 is under 5%, while its surface area decreased and pore structure is changed slightly if the V2O5 is above 5%.