A series of Cd1-xZnxS (x = 0.05-0.3) photocatalysts supported on ordered mesoporous silica (SBA-15) were prepared and investigated for hydrogen production from water splitting under visible light. Textural, structural and surface photocatalyst properties are determined by N-2 adsorption isotherms, UV vis, Raman and XPS and related to the activity results in hydrogen production. Raman and XRD results indicated a mutual interaction between Cd and Zn, forming nanoparticles of Cd1-xZnxS solid solutions. All Cd1xZnxS/ SBA-15 samples showed relatively high activities for hydrogen evolution. The hydrogen production rate is found to increase gradually when the zinc concentration on photocatalysts increases from 0.05 to 0.2, achieving a maximum for the photocatalyst with zinc concentration equal to 0.2. Variation in photoactivity is discussed in terms of modification in the conduction band and light absorption ability of Cd1-xZnxS particles derived from the changes in the Zn concentration in the Cd1-xZnxS solid solution. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.