Nano-composites of Au/Fe2O3 with different Au concentrations were prepared by a co-precipitation method. The microstructure and phase analysis of the nano-composites were carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The compositions of the powders were confirmed by energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). Band gaps of the powders were analyzed by UV-Vis spectroscopy. The photocatalytic property of the nano composites was analyzed for methylene blue (MB) degradation and the powders with 0.5 mol of Au show the best photocatalytic degradation efficiency toward methylene blue dye. Evaluation of the reaction conditions for Au(0.5)/Fe2O3 was also carried out at different process conditions such as reaction temperature, light intensity, and pH. (C) 2015 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.