NOVELTY - A hydrogen generator (100) has material provisioning portion which supplies raw material, water supply portion, modification portion (2) which generates hydrogen-containing gas, heating portion (1) which supplies heat required for reaction, transformation portion (3) provided with transformation catalyst which carries out transformation reaction of carbon monoxide, transformation cooling portion which controls entrance-side temperature of transformation portion and transformation water-cooled portion which controls exit side temperature of transformation portion.    USE - Hydrogen generator is used for fuel cell electric power generation apparatus (claimed).    ADVANTAGE - The hydrogen generator efficiently reduces the amount of carbon monoxide and controls the temperature of catalyst layer.    DETAILED DESCRIPTION - A hydrogen generator has material provisioning portion which supplies raw material, water supply portion which supplies water, modification portion containing modification catalyst which generates hydrogen-containing gas by modification reaction of raw material supplied from material provisioning portion and water supplied from water supply portion, heating portion which supplies heat required for modification reaction to the modification portion, transformation portion provided with transformation catalyst which carries out transformation reaction of carbon monoxide contained in hydrogen-containing gas which flowed out of modification portion, and water vapor, transformation cooling portion which controls the entrance-side temperature of the transformation portion after the inflow of hydrogen-containing gas by air cooling and transformation water-cooled portion which controls the exit side temperature of the transformation portion before the outflow of hydrogen-containing gas with water supplied from water supply portion.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view of the hydrogen generator. (Drawing includes non-English language text)    Heating portion (1)    Modification portion (2)    Transformation portion (3)    Hydrogen generator (100)    Water supply port (101)