Fore the first time, a novel BiOCl/CuS nanocomposite with a heterojunction structure was prepared by a one-step hydrothermal method. The BiOCl/CuS heterojunctions were used as photocatalyst for degradation of organic pollutants, such as rhodamine B (RhB), under visible light irradiation (lambda >420 nm). The results reveal that the heterojunction structure composite exhibits markedly improved efficiency and high photostability for the RhB photodegradation in comparison with pure BiOCl and pure CuS. This is ascribed to the heterojunction structure with an efficient charge separation and transfer across the BiOCl/CuS junction. Moreover, the catalytic activity is related to the ratio of CuS to BiOCl in the nanocomposite, and the BiOCl/CuS heterojunction in a 0.5:1 mol ratio exhibits the highest photocatalytic activity. According to experimental results, the photocatalytic mechanism of BiOCl/CuS photocatalyst is proposed to explain the improvement of the photocatalytic activity. (C) 2015 Elsevier B.V. All rights reserved.