Cu/ZnO/Al2O3 catalyst coatings have been prepared for a micro-channel reactor, which is more suitable for on-board production of hydrogen concerning steam reforming of methanol (SRM) for fuel cells compared to conventional systems. Several parameters that control the structural characteristics of the Cu/ZnO/Al2O3 catalyst coatings have been optimized in an annular micro-reactor that is similar to the micro-channel reactor in flow pattern, but is much simpler to be fabricated and can be used repeatedly. It was confirmed that catalytic activity was directly related to copper metal surface area. The catalyst COAT-14-6 (CuO 14 wt. % and ZnO 6 wt. %) that showed the highest copper area gave the best result for SRM. A micro-channel reactor was developed by diffusion bonding and wet chemical etching. The performance of the micro-channel reactor with the optimum Cu/ZnO/Al2O3 catalyst coating has also been investigated in a continuous reaction for 100 h. The result showed the micro-channel reactor could generate enough hydrogen for power output of 10 W. (c) 2005 Elsevier B.V. All rights reserved.