Crystalline tetragonal quasi-rounded AgGaS2 nanoplates with a diameter of about 40 nm were successfully synthetized by a facile one-pot hydrothermal process. The as-prepared product was characterized with X-ray diffraction, transmission electron microscopy, Xray photoelectron spectroscopy, N-2 adsorption-desorption isotherms and UV-vis spectroscopy. Meanwhile, photocatalytic H-2 evolution from water over the as-prepared AgGaS2 nanoplates loaded with CuS was explored using Na2S and Na2SO3 as sacrificial reagents. The results indicate that the AgGaS2 nanoplates loaded with CuS is an efficient photocatalyst under visible irradiation. More importantly, the photocatalytic H-2 evolution is very rapid in the presence of the AgGaS2 nanoplates with CuS. In the first hour of irradiation, more than 65% of the total hydrogen production can be obtained and the rate is up to 772 mu mol h(-1) g(-1). Furthermore, for practical purposes, the photocatalytic H-2 evolution was studied as a function of content of loaded CuS, hydrothermal reaction temperature, hydrothermal reaction time, dosage of photocatalyst, and concentration of sacrificial reagents, respectively. At last, the formation mechanism of AgGaS2 nanoplates and the photocatalytic mechanism were preliminarily discussed. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.