Abstract: Bi₂MoO₆/WO₃ composite photocatalysts with various Bi₂MoO₆ amounts were successfully synthesized by hydrothermal method. The microstructure, morphologies, optical absorption properties and spectral response of Bi₂MoO₆/WO₃ composites were measured and characterized by XRD, SEM, UV-Vis, EIS and PL. Moreover, the photocatalytic activities of the samples were further investigated. The results show that the photocatalytic activity of the 15%Bi₂MoO₆/WO₃ composite is obviously higher than that of the pure WO₃ and Bi₂MoO₆: the photocatalytic oxygen production efficiency of the Bi₂MoO₆/WO₃ is 2.3 times that of the pure WO₃. The oxygen production efficiency of composite catalyst obtained 107 μmol/(g·h) after introducing Fe(NO₃)₃·9H₂O assacrificial agent and exhibited good cycling stability. It is inferred that the Bi₂MoO₆ nanoparticle-WO₃ nanorod heterojunction structure improves the transport and transfer efficiency of photo-generated carriers, reduces the recombination probability of electron-hole pairs, which is helpful to enhance the photocatalytic activity.