Cu2O/crosslinked-chitosan nanocomposites (Cu2O/CS NCs) were in situ prepared via a simple one-step liquid phase precipitation-reduction process and characterized by XRD, FT-IR, SEM, TEM, BET, XPS and UV-vis/DRS. The characterization results showed that Cu2O/CS NCs were almost similar spherical or ellipsoidal and the surface was rough and porous because Cu2O particle was wrapped in chitosan. The chitosan layer was especially favorable for improving the adsorption ability of dye and molecular oxygen and restraining the recombination of electrons-holes pair. The visible-light photocatalytic decolorization behavior on Cu2O/CS NCs was evaluated using reactive brilliant red X-3B (X-3B) as a model pollutant. The influences of various experimental factors on X-3B decolorization were investigated. It was found that the photocatalytic decolorization process on Cu2O/CS NCs followed apparent pseudo-first-order kinetics model. The dye X-3B could be decolorized more efficiently in acidic media than in alkaline media. Cu2O/CS NCs exhibited enhanced visible-light photocatalytic activity compared with other photocatalysts reported before under similar experimental conditions. (C) 2013 Elsevier B.V. All rights reserved.