In this work, BiVO4 powders were synthesized by a sol-gel method, and the BiVO4 gels with different calcination temperature were investigated by X-ray diffraction (XRD). Absorption range and band gap energy, which are responsible for the observed photocatalyst behavior, were investigated by UV/vis diffuse reflectance spectroscopy (DRS) for pure and silver oxide loaded BiVO4. Photocatalytic properties of the prepared samples were examined by studying the degradation of the methyl orange. When using NaClO2 as an electron acceptor, the possible photocatalytic mechanism has been discussed by photocatalytic reactions. With the help of electron acceptor, the results show clearly that the BiVO4 loaded silver oxide exhibited superior photocatalytic activity in simulated dye wastewater treatment. (C) 2014 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.