Abstract: TiO2 nanotubes were fabricated by two-step anode oxidation method,and CdSe was deposited on the nanotubes by potentiodynamic deposition.Scanning electron microscopy (SEM),X ray diffraction (XRD) test methods were used to observe the surface morphology and phase characteristics of the composite material.According to the open circuit potential (OCP),electrochemical impedance spectroscopy (EIS),Tafel polarization curve and other electrochemical methods,the optical properties of the composite and its cathodic protection effect on 304 stainless steel were investigated.The results showed that,under visible light irradiation,the open circuit potential of 304 stainless steel shifted from -190 mV(SCE)to -500 mV(SCE),after turning off the light,the electrode potential slowly increased to about -220 mV(SCE),and it showed a protective effect on stainless steel in dark environment.In the visible range,the cathodic protection performance of CdSe-TiO2 composite material was significantly improved compared with pure TiO2.