MoS2 nanoparticles modified TiO2 nanobelts (TiO2-MoS2) with tunable decoration amount of MoS2 nanparticles have been successfully synthesized via a two-step hydrothermal method, which involves preparation of TiO2 nanobelts and decoration of the MoS2 nanoparticles. The as-prepared samples were carefully characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray and detector (EDX), X-ray photoelectron spectroscopy (XPS), respectively. The photocatalytic activity of the as-prepared samples was evaluated by photocatalytic degradation of Rhodamine B (RhB) under visible light irradiation. The photocurrent measurement was also tested to confirm the results of photocatalytic activity. It can be found that TiO2-MoS2 heterojunction structures with MoS2 decoration amount of 40 wt% (TM-4) possess the highest photocatalytic activity since it has the suitable amount of MoS2 for prohibiting the recombination of photogenerated electrons and holes. In addition, highly apparent photocatalytic reaction rate constant of TM-4 is about 4.78 times than that of pure TiO2 nanobelts. (C) 2014 Elsevier B.V. All rights reserved.