A catalytic decalin dehydrogenation/naphthalene hydrogenation pair has been proposed as a hydrogen source for fuel-cell vehicles in the present study. In order to evolve hydrogen from decalin efficiently under mild conditions, its catalytic dehydrogenation in a liquid-film type reactor was adopted with use of carbon-supported platinum-based fine particles under reactive distillation conditions. The catalyst layer was superheated in the liquid-film state,which gave much higher hydrogen evolution, rates and conversions at 210degreesC than those in the suspended state Requirements concerning high-evolution rates of hydrogen or high-power densities for practical fuel-cell vehicle operations would be fulfilled enough at around 280degreesC. As for the storage densities of hydrogen on both weight and volume bases (7.3 wt%, 64.8 kg-H-2/m(3)), it is to be noted that their magnitudes are higher than the storage densities (6.5 wt%, 62.0 kg-H-2/m(3)) targeted by the Department of Energy, USA (DOE). (C) 2003 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.