Nitrogen doped titanium dioxide nanoparticals (N-TiO2) were prepared by the sol-hydrothermal method using urea as N sources. SEM showed the sphericity of as-prepared nanoparticals. XRD indicated that N-TiO2 was anatase crystal after thermal treatment. While Na-chlorophyllin copper (Na-chl-Cu) was used as to sensitize the N-TiO2, the photocurrent of Na-chl-Cu/N-TiO2 was 50 ìA double than that of N-TiO2 under visible light illumination. Thus, the visible light photoelectrocatalytic degradation properties of Na-chl-Cu/N-TiO2 were investigated using methyl orange (MO) as the objective pollution. When 1.8 V anodic bias potential and visible light were simultaneously applied, the highest degradation efficiency of MO over the Na-chl-Cu/N-TiO2 was obtained.