BiOBr-g-C3N4 inorganic-organic composite photocatalysts were synthesized by a one-step chemical bath method at low temperature and characterized by X-ray diffraction patterns (XRD), Fourier transform infrared (FT-IR), thermo gravimetric (TG), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM) and UV-vis diffuse reflectance spectra (DRS). The BiOBr-g-C3N4 composite showed much higher visible-light-driven (VLD) photocatalytic activity than pure g-C3N4 and BiOBr for rhodamine B (RhB) degradation. The photocatalytic mechanism analysis revealed that the interreaction between BiOBr and g-C3N4 is a kind of facet coupling between BiOBr-{0 0 1} and g-C3N4-{0 0 2}. The active species trapping and quantification experiments indicated that the photoinduced charges transfer between these facets resulted in the efficient charge separation. Crown Copyright (c) 2013 Published by Elsevier B.V. All rights reserved.