H-2 evolution was observed for the first time from a photoelectrochemical cell using an n-type Cu2O photoelectrode under visible light irradiation. Three-electrode configuration was used in the photoelectrochemical cell to observe H-2 evolution. AgCl/Ag calomel electrode and a platinum plate were used as the reference and counter electrodes, respectively. Fe2+/Fe3+ redox couple was used as the electrolyte. H-2 evolution was visible on the platinum electrode in the photoelectrochemical cell.