a b s t r a c tIn this work, Bi 2 S 3 /SnS 2 heterojunction photocatalysts were prepared by combining a hydrothermal technique and a facile in situ growth method. The nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma spectroscopy, X-ray photoelectron spectroscopy, UVeVis diffusion reflectance spectroscopy and roomtemperature photoluminescence spectra. Their photocatalytic performances were evaluated by degrading methyl orange (MO) in aqueous solution (50 mg/L) under visible light (l > 420 nm) irradiation. It was found that when the mass percentage of Bi 2 S 3 in Bi 2 S 3 /SnS 2 was 7.95 wt%, the as-prepared Bi 2 S 3 / SnS 2 nanocomposite showed the best photocatalytic activity for the degradation of MO. The highly improved performance of the Bi 2 S 3 /SnS 2 nanocomposite was mainly ascribed to the efficient charge separation.