The fabrication of novel ZnSnO3 hollow nanospheres/reduced graphene oxide (RGO) hybrid nanocomposite is reported for the first time. The nanocomposites were synthesized via a facile route, and were well characterized with the aid of XRD, FUR, SEM, TEM, BET, UV-vis, and PL techniques. Moreover, the synthesized nanocomposites were used as photocatalysts in the application of the degradation of pharmaceutical wastewater. In this study, ZnSnO3 hollow nanospheres showed high efficiency in photocatalytic degradation of metronidazole under ultraviolet (UV) light irradiation. More interestingly, the photocatalytic activities of these nanospheres could be enhanced by coupling with RGO, where a large improvement (approx. 30.4% increase compared with pure ZnSnO3) in photodegradation of metronidazole was observed on the prepared ZnSnO3/RGO hybrid nanocomposites under visible light irradiation. This improvement might be attributed to the advanced adsorption efficiency of molecules and enhanced visible light absorption within the hybrid nanocomposites by the introduction of RGO. Such study might pave the way toward designing novel photocatalyst systems for efficient degradation of pharmaceutical wastewater. (C) 2013 Elsevier B.V. All rights reserved.