CuO/TiO2 nanoparticles were prepared with hydrothrmal method and characterized by means of X-ray diffraction (XRD) and Transmission electronmicroscopy (TEM). The photocatalytic properties of the immobilization of CuO/TiO2 nanoparticles were assessed by measuring the photodegration of Rhodamine 6G in aqueous solution. These immobilization of CuO/TiO2 nanoparticles showed much higher photoactivity than immobilization of TiO2 nanoparticles. Results of this study also indicate that the photodegradative mechanisms are that the doping of Cu2+ in TiO2 nanoparticles made the ability of TiO2 particles adsorbed Oxggen enhance, and decreaded the recombination of photogenerated electrons and photogenerated hole in the interface of nanoparticles. Therefore the photogenerated reactions were accelerated. In addition, the results that the polluted water was treated with CuO/TiO2 nanoparticles wre exciting and promising.