Ion doping is regarded as an effective method to improve the intrinsic properties of semiconductor photoanode. In this paper, Bi-doped Ti/Co 3 O 4 NWs with n-type characteristics were prepared by one-step hydrothermal method and applied into photoelectrocatalystic (PEC) decolorization of dyeing wastewater (reactive brilliant blue KN-R). By adjusting the content of bismuth, the performance of the Ti/Co 3 O 4 NWs can be optimized, and the physicochemical properties of as-obtained electrodes were also characterized by XRD, TEM, SEM, XPS, EDS and so on. It is found that the Bi doping can tune the morphology of Ti/Co 3 O 4 NWs, and enhance the PEC activity of Ti/Co 3 O 4 NWs. Furthermore, the Bi-doped Ti/Co 3 O 4 electrode exhibited obvious photoelectric synergism and good reproducibility. The improvement of PEC performance for Bi-doped Ti/Co 3 O 4 NWs can be ascribed to its higher efficiency of generating hydroxyl radical, better conductivity and more active sites.