NOVELTY - A fuel reforming device comprises autothermal reforming reactor (110) for performing autothermal reforming reaction on fuel supply (150) to obtain first reformed gas (152); steam reforming reactor (120) for performing steam reforming reaction on fuel supply to obtain second reformed gas (154); and heating unit (140) for heating the fuel supply and steam reforming reactor. The device mainly performs autothermal reforming reaction at the beginning period of operation to shorten catalytic reforming reaction time, and after reaching stable operation, it mainly performs steam reforming reaction.    USE - Fuel reforming device used in hydrogen-generating device for producing hydrogen gas employed in, e.g. fuel cell (claimed).    ADVANTAGE - The fuel reforming device is efficient and can provide hydrogen gas with low carbon monoxide content.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for:    (A) a hydrogen-generating device comprising the fuel reforming device; a water-gas shift reaction unit for reacting water and carbon monoxide contained in the second reformed gas to convert them into carbon dioxide and hydrogen gas so as to obtain a first output gas; and a selective oxidation reaction unit for selectively performing oxidation reaction of carbon monoxide contained in the first output gas or hydrogen to obtain a second output gas; and    (B) a fuel reforming technique for fuel cell, comprising (a) providing a fuel supply and a reforming reaction unit comprising an autothermal reforming catalyst and a steam reforming catalyst; (b) starting a burner to heat the reforming unit and the fuel supply; (c) feeding fuel into the autothermal reforming catalyst when the temperature at the feeding port of the autothermal reforming catalyst reaches 90-200 degrees C to produce first reformed gas; (d) introducing the fuel into the steam reforming catalyst to produce second reformed gas; (e) performing water-gas shift reaction and selective oxidation reaction on the first and second reformed gases to produce an output gas; (f) when the concentration of carbon monoxide in the output gas is lower than 20 ppm, feeding the output gas into the anode of the fuel cell, otherwise, feeding the output gas into the burner; and (g) when the temperature of the combustion exhaust gas flowing through the outer side of the autothermal reforming catalyst reaches 650-750 degrees C, stopping feeding fuel and providing air so that the reforming reaction unit mainly operates with the steam reforming catalyst.    DESCRIPTION OF DRAWING(S) - The drawing is a schematic sectional view illustrating the fuel reforming device.    Autothermal reforming reactor (110)    Steam reforming reactor (120)    Heating unit (140)    Fuel supply (150)    First reformed gas (152)    Second reformed gas (154)