NOVELTY - A hydrogen production apparatus (1) comprises modifier (12) which performs modification process by making reformed gas containing hydrocarbon react with water vapor and produces reformed gas containing hydrogen gas, carbon monoxide and carbon dioxide, transformer (13) which produces conversion gas containing low carbon monoxide concentration, and combustor (16) which discharges combustion exhaust gas after combustion outside while burning predetermined combustion gas supplied and performing heat supply with respect to modifier.    USE - An apparatus for production of hydrogen used for fuel cell.    ADVANTAGE - The apparatus has high thermal efficiency and reduced size, and produces hydrogen steadily.    DETAILED DESCRIPTION - A hydrogen production apparatus (1) comprises modifier (12) which performs modification process by making reformed gas containing hydrocarbon react with water vapor and produces reformed gas containing hydrogen gas, carbon monoxide and carbon dioxide, transformer (13) which produces conversion gas containing low carbon monoxide concentration by reacting carbon monoxide contained in reformed gas with water vapor and transforming to carbon dioxide, combustor (16) which discharges combustion exhaust gas after combustion outside while burning predetermined combustion gas supplied and performing heat supply with respect to modifier, cylindrical body formed on axial center extended to perpendicular direction, channel for heat exchange (33, 34) which communicates lower base part and upper base part of cylindrical body, and denaturation catalyst filled inside channel for first heat exchange. The transformer comprises lower stage part. The modifier and combustor comprise upper stage part in upper side of lower stage part.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic block diagram of hydrogen production apparatus. (Drawing includes non-English language text).    Hydrogen production apparatus (1)    Modifier (12)    Transformer (13)    Combustor (16)    Channel for heat exchange (33, 34)