A series of ceria promoted copper based nanocatalysts were synthesized by conventional and sonochemical co-precipitation methods at different irradiation power and time. Their performance was investigated for fuel cell-grade hydrogen production from methanol. The nanocatalysts were characterized by X-ray diffraction, field emission scanning microscope, Fourier transform infrared spectroscopy, specific surface area, and energy dispersive X-ray analyses. According to crystallography analysis by increasing irradiation power and time, the copper oxide crystallinity reduced and smaller and fully dispersed crystals produced. The nanocatalyst which sonicated at 90 W for 15 min had small spherical nanoparticles which their size range varied between 1 nm to 125 nm. The performance of nanocatalysts was examined through the methanol steam reforming process at 160-260 degrees C and atmospheric pressure with space velocity of 10,000 cm(3)/g(cat) h in a U-shape fixed bed reactor. Among all nanocatalysts, the sample synthesized by conventional co-precipitation showed the weakest activity. But the others which synthesized by the ultrasound assisted co-precipitation method represented higher activity in terms of methanol conversion as the irradiation power and time enhanced. Complete methanol conversion achieved at 200 degrees C for the nanocatalyst which sonicated at 90 W for 15 min during co-precipitation which is ideal for application in fuel cell vehicles. (C) 2016 Elsevier Ltd. All rights reserved.