NOVELTY - An integrated cylinder type water vapor modifier has a modification-catalyst layer, a carbon monoxide-modifying catalyst layer (22) and a carbon monoxide removal catalyst layer (36) integrated and provided in a cylindrical container. The air is mixed with a reformed gas which passed through the modification-catalyst layer and carbon monoxide-modifying catalyst layer, and supplied to the carbon monoxide removal catalyst layer. The integrated cylinder type water vapor modifier has partition plate (a and b) (51,54).    USE - Integrated cylinder type water vapor modifier is used for supplying fuel hydrogen to polymer electrolyte fuel cell (claimed).    ADVANTAGE - The integrated cylinder type water vapor modifier is manufactured economically. The fluctuation of temperature-distribution difference in the integrated cylinder type water vapor modifier is reduced.    DETAILED DESCRIPTION - An integrated cylinder type water vapor modifier has a modification-catalyst layer, a carbon monoxide-modifying catalyst layer (22) and a carbon monoxide removal catalyst layer (36) integrated and provided in a cylindrical container. The air is mixed with a reformed gas which passed through the modification-catalyst layer and carbon monoxide-modifying catalyst layer, and supplied to the carbon monoxide removal catalyst layer. The integrated cylinder type water vapor modifier has partition plate (a and b). The partition plate (a) has reformed-gas flow-hole between carbon monoxide-modifying catalyst layer and carbon monoxide removal catalyst layer. The partition plate (b) has reformed-gas flow-hole between partition plate (a) and carbon monoxide-modifying catalyst layer, between partition plate (a) and partition plate (b), the partition plate (a) and partition plate (b) has space between partition plate (b) and carbon monoxide removal catalyst layer respectively. The reformed-gas flow-hole of the partition plate (a) and reformed-gas flow-hole of the partition plate (b) are provided in opposite-in circumferential direction side.    DESCRIPTION OF DRAWING(S) - The drawings show the sectional view of the integrated cylinder type water vapor modifier. (Drawing includes non-English language text)    Cylindrical components (2,4)    Carbon monoxide-modifying catalyst layer (22)    Air supply pipe (30)    Carbon monoxide removal catalyst layer (36)    Partition plates (51,54)