A novel mini-reactor for hydrogen production has been successfully fabricated, which integrates one reforming chamber, one catalytic combustion chamber and two preheating chambers. It can be started up at room temperature by the combustion of liquid methanol in the combustion chamber within 10 min, and it also can keep self-sustained, i.e. without any external heating during the operating process. This reactor has been tested for carrying out the reaction of autothermal reforming of methanol for hydrogen production. The reactor performance has been investigated using three crucial parameters, namely, the molar ratios of water/methanol, oxygen/methanol and the flow distribution, respectively. The experimental runs have demonstrated the optimal methanol conversion of 96.4%, containing 51.04% H-2, 26.68% N-2, 2.12% CO and 20.16% CO2 in the reformed gas. Furthermore, the reformer which can supply reformed gas at the maximum flow rate of 1251 (STP)/h has been integrated with a miniature fuel cell, the small power system can produce continuous power at the energy density of 92 mW/cm(2) for 4h. (C) 2007 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.