In this study, we report controllable synthesis of ZnS-Ag2S composite microspheres by the two-step hydrothermal method, which demonstrate excellent photocatalytic properties. Structure and morphology evolutions are investigated by adjusting the weight ratios of ZnS precursor and AgNO3. Photocatalytic properties of the obtained samples are investigated by the photodegradation analysis of methylene orange (MO) dye. Surface modification of ZnS spheres by Ag2S leads to highly enhanced photocatalytic activity, in comparison to pure ZnS. Furthermore, this method could be extended to prepare other sulfide based composite catalysts. (c) 2013 Elsevier B.V. All rights reserved.