It was difficult to acquire a good CO cleanup efficiency in a hydrogen refining apparatus, for instance, when the start-up and stop operations are frequently repeated.A hydrogen refining apparatus, including a shifter having a shifting catalyst body containing noble metals and metal oxides, and a reforming section for supplying hydrogen gas containing carbon monoxide to the shifter, (1) the temperature of an upstream side of the shifting catalyst body relative to the hydrogen gas flow being substantially between 300.degree. C. and 500.degree. C. and (2) the temperature of a downstream side of the shifting catalyst body relative to the hydrogen gas flow being substantially at 300.degree. C. or less.