In the present work, we demonstrate the photocatalytic properties of nanosized TiO2, and different levels of ZnS-loaded TiO2/ZnS composites, for the degradation of the organic dyes brilliant green (BG), and methylene blue (MB) under solar light irradiation. For this process, TiO2 and the composites were synthesized by a sol-gel method. Further, the prepared products were subjected to structural, optical, and morphological characterizations. The results of the photocatalytic activity imply that for the samples studied, TiO2 loaded with an optimum level of zinc (0.25 M), and sulfur (0.5 M) is better able to actively degrade both BG and MB, due to its enhanced BET surface area, reduced band gap, and low charge transfer resistance. (C) 2016 Elsevier B.V. All rights reserved.