In this study, rGO/WO3 nanocomposites were synthesized by one-pot hydrothermal method for photocatalytic applications. Properties of the synthesized materials were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), UV–Vis absorption spectra and Fourier-transform infrared spectroscopy (FTIR). XRD analysis documented the formation of the hexagonal phase WO3 with high crystalline quality. SEM images revealed that the WO3 nanorods and layered rGO materials were synthesized. The band gap of the rGO/WO3 composite calculated from the UV–vis spectra was about 2.7 eV which is smaller compared to that of bare WO3 (3.1 eV). Photocatalytic results under UV light irradiation showed that the rGO/WO3 nanocomposite exhibited significantly higher photocatalytic activity than WO3, where the rGO/WO3 and WO3 degraded about 80% and 55% of methylene blue within 100 min under UV irradiation, respectively.