Defects are ubiquitous in oxide supports and can often tune the catalytic property of supported metal catalysts.This work describes the distinct role of titanium and oxygen vacancies of TiO2 supports in the catalytic performance of supported Pt catalysts for CO oxidation.Pt was loaded on the TiO2 supports with oxygen vacancies (Vo-TiO2) and titanium vacancies (VTi-TiO2).It was found that different defects of TiO2 could distinctively modify the electron property of Pt and thereby CO adsorption strength.The strength of CO adsorption on Pt/VTi-TiO2 is enhanced,while that of Pt/Vo-TiO2 becomes weaker.Additionally,the presence of defects would also promote the reducibility of catalysts.On the account of the superior redox ability,both Pt/VTi-TiO2 and Pt/Vo-TiO2 exhibit a higher activity than Pt supported on normal TiO2 for CO oxidation.