Photocatalytic decomposition characteristics of three different single-component organic dyes and their mixture using microwave/UV/O-3/H2O2/TiO2 photocatalysts hybrid process system were investigated in this study. The decomposition rates of all organic dyes were higher in single-component experiments than in mixed solution experiments. The decomposition rates of all organic dyes increased with the ozone injection rate. The decomposition rate increased with increasing hydrogen peroxide concentration until it reached a maximum point beyond which it decreased with increasing hydrogen peroxide concentration. The result demonstrates that combination of elemental techniques that have little effect when used alone can make a synergy effect. (C) 2010 Elsevier B. V. All rights reserved.