A method for producing hydrogen

When the organic substance producing hydrogen reforming, by adding exhaust gas (G0) containing carbon monoxide generated in the metallurgical furnace excess steam to the shift reaction, the shift reaction is made containing hydrogen and carbon dioxide generated in the gas, and steam mixed gas not consumed in the reaction (g) transferring, by contacting the gas mixture (g) with an organic substance, the organic substance of the molecular weight of the reforming reaction, by reaction of the reformer is generated product steam reforming, hydrogen is generated.