For the first time, lepidocrocite-granular activated carbon (gamma-FeOOH-GAC) nano composite was prepared and characterized. The prepared composite was used in the decolorization of textile wastewater containing reactive orange 29 by photo Fenton-like process in a continuous reactor. The influence of wastewater flow rate, H2O2 concentration and pH in decolorization process was studied using response surface methodology. The optimum conditions were flow rate of 1.98 mL min(-1), H2O2 concentration of 3.25 mM and pH of 1.98. The decolorization ability of gamma-FeOOH-GAC/H2O2/UV process was compared with that of gamma-FeOOH-GAC/UV, gamma-FeOOH-GAC/H2O2, gamma-FeOOH-GAC, H2O2/UV, and UV processes at the optimum conditions. The obtained results indicated that gamma-FeOOH-GAC/H2O2/UV process was more effective than other processes in the decolorization of the wastewater. (C) 2014 Elsevier B.V. All rights reserved.