Biomass is an important energy resource in terms of renewable resource and carbon neutral material. Fermented organic compounds to obtain ethanol include high concentration of water and low concentration of ethanol. Such biomass ethanol has to be distilled with an enormous amount of energy consumption before adding it into gasoline. A new approach to use biomass ethanol with water is hydrogen production by steam reforming of ethanol without distillation. We found that Co/SrTiO3 and Co/alumina catalyst had high activity for steam reforming of ethanol at 823 K. Also we investigated the reaction path from ethanol to hydrogen, promoting effect of small amount of Fe. As a result, we found that an addition of small amount of iron onto the Co catalyst promoted the steam reforming of acetaldehyde to produce hydrogen and CO, CO2.