Abstract In order to develop highly efficient visible-light induced photocatalysts, Bi2WO6 powders and mesoporous carbon (MC)-modified Bi2WO6 (MC/Bi2WO6) photocatalysts were synthesized via a simple hydrothermal process in this paper. The samples of Bi2WO6 and MC/Bi2WO6 were characterized by X-ray diffraction (XRD), UV–visible spectroscopy, scanning electron microscopy (SEM) and BET surface area analysis, and their photocatalytic activity were evaluated by photocatalytic decoloration of rhodamine B (RhB) aqueous solution under visible light. It was found that the presence of MC could significantly improve the crystallization of Bi2WO6 species and photoabsorption property of Bi2WO6 in the visible region. The results also showed that the BET surface areas of MC/Bi2WO6 composites were larger than that of the pure Bi2WO6 and the photocatalytic activity of the MC/Bi2WO6 is much higher than that of Bi2WO6 with the optimum effect occurring at RMC=0.10 (the weight ratio of MC to Bi2WO6). Close investigation revealed that the surface area, grain size and charge transfer of the as-prepared MC/Bi2WO6 composites could improve the photocatalytic activities.