WO₃ with 3D hierarchical structure was successfully grown into the TiO₂ nanotube arrays (TiO₂ NTs) on Ti substrate by two-steps procedure. First, TiO₂ NTs were fabricated through anodization of titanium, and then WO₃ nanoparticles were deposited into the TiO₂ NTs and the WO₃ with 3D hierarchical structures were deposited on the top surface of TiO₂ NTs through hydrothermal method. The WO₃/TiO₂ composite photoelectrode showed better photoelectric response in visible light compared with the pristine TiO₂ and WO₃ electrodes. A higher photocurrent density was achieved by optimizing the experimental conditions including solution concentration, hydrothermal time and reaction temperature in details. The improvement of photoelectrochemical (PEC) response for WO₃/TiO₂ composite photoelectrode also indicated an important synergy between visible light absorption and 3D hierarchical structure inherent to WO₃ and the new formed semiconductor composite structures fabricated by hydrothermal treatment, which offers a significant improvement in the separation and transmission of photo generated electrons.