NOVELTY - A hydrogen generating apparatus (A) comprises hydrogen gas separation unit (B1-B3) which provides hydrogen separation body consisting of hydrogen-permeable membrane, state detection part (C) to detect operating state for every hydrogen gas separation unit, deterioration judging part which determines deterioration state for every hydrogen gas separation unit based on detection result of greater than or equal to 1 of the detection results, regeneration processing part (E) which regenerates every hydrogen gas separation unit based on deterioration state, and operation control part (F).    USE - A hydrogen generating apparatus for vehicle which mounts internal combustion engine, exhaust apparatus, and fuel cell.    ADVANTAGE - Hydrogen generating apparatus can maintain required hydrogen gas production amount even when hydrogen-permeable membrane deteriorates and has prolonged service life.    DETAILED DESCRIPTION - A hydrogen generating apparatus (A) comprises hydrogen gas separation unit (B1-B3) which provides hydrogen separation body consisting of hydrogen-permeable membrane, state detection part (C) to detect operating state for every hydrogen gas separation unit, deterioration judging part which determines deterioration state for every hydrogen gas separation unit based on detection result of greater than or equal to 1 of the detection results, regeneration processing part (E) which regenerates every hydrogen gas separation unit based on deterioration state, and operation control part (F) which operates independently each hydrogen gas separation unit. Regeneration processing part performs regeneration processing of 1 part of hydrogen gas separation units. During regeneration processing of 1 part of hydrogen gas separation unit, operation control part increases the amount of fuel gas supplied to the other hydrogen gas separation unit by which regeneration processing is not performed so that the required hydrogen gas production amount is satisfied, and hydrogen gas separation unit is operated.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of a hydrogen generating apparatus. (Drawing includes non-English language text).    Hydrogen generating apparatus (A)    Hydrogen gas separation unit (B1-B3)    State detection part (C)    Regeneration processing part (E)    Operation control part (F)