To provide a device for producing a fuel gas for a fuel cell, in which the fuel cell is stably operated while the heat exchange efficiency in an evaporator is kept high.

The device for producing the fuel gas for the fuel cell is provided with a combustor (catalytic combustor 4), the evaporator 5, a reformer 1 and a CO remover 2, a 1st pressure control means (a control valve 11) for controlling the pressure of the combustion gas supplied to the evaporator 5 is arranged in a combustion gas discharge passage 10 for discharging the combustion gas of the evaporator 5, a 2nd pressure control means (control valve 15) for controlling the pressure of the combustion gas supplied to the fuel cell 3 is arranged in a combustion gas discharge passage 9 on the downstream side of the fuel cell and the upstream side of the combustor (catalytic combustor 4) and the 1st pressure control means (control valve 11) and the 2d pressure control means (control valve 15) are controlled corresponding to the quantity related to the output of the fuel cell 3.