Polyaniline (PANI)-ZnS composite photocatalysts with high photocatalytic hydrogen production activity were synthesized via a solvothermal method. Surface chemistry, crystalline property, optical property, surface morphology, surface area, photocurrent, and photocatalytic activity of the photocatalysts were characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy, photoelectrochemical (PEC), BET, FTIR, and photocatalytic H-2 production tests. Incorporation of the conductive polymer PANI can help the separation of photogenerated charge through the PANI-ZnS interfaces in the photocatalysis process and enhance the photocatalytic activity and stability of the PANI-ZnS photocatalysts. In addition, the dispersing stability of the composite photocatalysts in water was also improved. The P-ZnS-40 photocatalyst with 40 wt% PANI exhibits optimized photocatalytic H-2 production rate of 6570 mu mol h(-1) g(-1). After 3 cycles, the photocatalytic activity of the recycled photocatalyst remained at about 96% of its original activity for the first run. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.