NOVELTY - The hydrogen separation apparatus (B1) has several hydrogen-containing gas generating elements (30) and several hydrogen-permeation elements (40) that are arranged opposing to each other in distribution path of fuel gas. The fuel gas flowing through the path is hydrogen-containing gas such as hydrocarbon gas and/or alcoholic gas.    USE - Hydrogen separation apparatus for fuel cell system of internal combustion engine system (both claimed) used in motor vehicle.    ADVANTAGE - Since generation of hydrogen-containing gas and separation of hydrogen gas are performed simultaneously, enlargement of the apparatus is eliminated and cost reduction is enabled. Uniform heat distribution is enabled by the heater, and electric power generation efficiency is improved.    DETAILED DESCRIPTION - The apparatus has hydrogen recovery path (50) for collecting and discharging hydrogen gas transmitted from the hydrogen-permeation elements. An electric heater is provided in the outer side of hydrogen recovery path for heating hydrogen-containing gas generating element. The element is included with catalyst layer. The heater is provided with combustion type catalyst layer. A pair of heaters is connected to the hydrogen-containing gas generating element. A heat conducting fin is provided in the hydrogen recovery path. INDEPENDENT CLAIMS are included for the following:    (1) fuel cell system which includes fuel cell main structure used for generating electric power by utilizing hydrogen gas; and    (2) internal combustion engine system which includes mixer for mixing the fuel and the hydrogen gas. The fuel and hydrogen gas mixture is then supplied to internal combustion engine. An exhaust-gas purification apparatus is used to purify the exhaust gas discharged from the engine, after mixing the hydrogen gas with the exhaust gas.    DESCRIPTION OF DRAWING(S) - The drawing shows the perspective view of the hydrogen separation apparatus, and schematic view explaining the arrangement of hydrogen-containing gas generating elements and hydrogen-permeation elements. (Drawing includes non-English language text)    Exhaust passage (12)    Hydrogen-containing gas generating element (30)    Hydrogen-permeation element (40)    Hydrogen recovery path (50)    Hydrogen separation apparatus (B1)