Here we reported a facile approach to synthesize Cu2O/Cu composite particles by one-step sono-chemical process. The content of Cu in the Cu2O/Cu composites can be easily controlled by adjusting the synthesis time. Phase, morphology and optical properties of the products were carried out by X-ray diffraction (XRD), field-emission scanning electron microscopy (FSEM), transmission electron microscope (TEM), ultraviolet-visible (UV-vis) spectroscopy and nitrogen adsorption apparatus. Using photocatalytic degradation of Methyl orange (MeO) dye under visible-light illumination, we have investigated the influence of Cu on the photocatalytic activity of Cu2O, to find out its potential application in waste water treatment. Especially, the stability of the photocatalyst was confirmed using reclaimed Cu2O/Cu in ten successive runs. Results demonstrated clearly that Cu2O/Cu were stable and resistant to photocorrosion during the photocatalytic oxidation of organic compounds, indicating that these Cu2O/Cu composites are promising candidates for pollutant processing.