In this paper, a novel approach for photoelectron-catalytic hydrogen production under visible light irradiation using tungsten oxide as photocatalyst is studied. A tungsten oxide thin film with an average thickness of 50 μm was successfully fabricated on a tungsten foil substrate. The film is dense, uniform and robust, which provides benefit in applications such as catalysis and photoelectrocatalytic water splitting. Hydrogen production experiments were carried out both indoor (with a 300 W Xe lamp as the light source) and outdoor. The tests confirmed that the tungsten oxide catalyst showed high photocatalytic performance toward water splitting under natural light irradiation. A solar-to-hydrogen efficiency of 3.76% was achieved in this system adding oxalic acid as a sacrificial agent under natural sunlight irradiation.