We report the one-step synthesis of MoO3-supported SnO2 composite using a wet chemical method. The structural features of the composite with respect to the MoO3 content are discussed. The composites were characterized using X-ray diffraction, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FTIR), UV-vis diffuse reflectance spectroscopy, thermal-gravimetric and differential thermal analysis (TG-DTA), Raman spectroscopy, high resolution X-ray photoelectron spectroscopy (XPS) and BET surface area analysis. 2.5 mol% MoO3-supported SnO2 sample has higher surface area of 51.6 rn(2)g(-1) than that of pure SnO2, 1 and 5 mol% MoO3-supported SnO2 samples. The photocatalytic degradation of Rhodamine B (RhB) using the MoO3-supported SnO2 composite under UV light irradiation is reported. The photocatalytic properties were also studied with different concentrations of MoO3, and the influence of morphology on the photocatalytic activity was elucidated. The active edges of MoO3 could promote UV absorption for reactant diffusion. The heterogeneous structure with different energies improved and facilitated charge separation and enhanced the photocatalytic activity compared to pure SnO2, MoO3. The MoO3-supported SnO2 photocatalyst shows good photostability and easy recovery from dye for recycling.