PURPOSE: To renew the catalyst packing density which becomes coase due to the reduction operation to be dense and to prevent the generation of particles of catalyst by providing a catalyst pressing mechanism pressing the catalyst through a pressing plate which is permeable for the reforming gas, to the end surface of reforming gas outlet side of reforming catalyst layer in a cylindrical vessel.

CONSTITUTION: In the heated state of an evaporator 17 and a reactor 6, the reforming raw material consisting of methanol and water is supplied from an inlet 18 in the direction shown by an arrow 25, and evaporated at the evaporator 17, and the evaporated gas is sent through a raw material manifold 19 to a raw material gas inlet 6a of the lower end part of the reactor 6. This raw material gas is brought into contact with the catalyst 10 while ascending in the reactor 6 to be reformed. Before the reforming device is put into operation, the reduction operation for the catalyst 10 is carried out and the volume of the catalyst is reduced with the result that the packing density of the catalyst 10 becomes coase. Therefore, the upper end surface of catalyst layer is gradually pressed down by the pressing plate 22 and the packing density of the catalyst 10 is raised, and the fluidization of the catalyst 10 and the grinding of the catalyst 10 due to the movement of reforming device are restrained.