NOVELTY - The desulfurizer has container (1) for forming fuel channel. The desulfurizing agent layer (2) is filled in container with desulfurizing agent. The heater (3) is arranged at center or outer peripheral portion of desulfurizing agent layer. The heat-conducting fin (10) is made to contact the heater thermally while extending in the direction to which center portion and outer peripheral portion of desulfurizing agent layer are tied. The heat-conducting fin is provided with bigger opening portion than the desulfurizing agent.    USE - Desulfurizer used for desulfurization of liquid fuel e.g. kerosene oil and gaseous fuel, used in hydrogen production apparatus of fuel cell system. Can also be used in town gas, liquefied petroleum gas (LPG), and alcohol fuel.    ADVANTAGE - The heat of the heater can be efficiently transmitted throughout the center portion and outer peripheral portion, thus the temperature difference of center portion and outer peripheral portion can be eliminated. The desulfurizing agent can be utilized effectively and the lifetime of desulfurizer can be improved. The blocking of desulfurizing agent during the manufacturing time can be prevented. The equalization of the temperature can be attained.    DETAILED DESCRIPTION - The desulfurizer has heat-conducting fin that is made to contact the heater thermally by center side and is connected with inner wall of container thermally by outer peripheral side, when the heater is arranged at center portion of desulfurizing agent layer. The outer side ring portion is connected with inner wall of container. The inner side ring portion and outer side ring portion are connected radially from several ribs. The opening portion is provided between the ribs. The heat-conducting fin is provided with center hole for connecting heater arranged at center portion of desulfurizing agent layer, and with outer edge portion for connecting inner wall of container. The outer wall of container is mounted in the heater. The heat-conducting fin is made to connect external heater through wall portion of container by outer peripheral side. The fuel inlet tube is made to penetrate desulfurizing agent layer. The edge portion is opened to upstream of desulfurizing agent layer. The heat-conducting fin is set by flow direction of fuel in desulfurizing agent layer. The heat-conducting fin is extended from heater arrangement side of outer periphery of the desulfurizing agent layer to the other side of outer periphery of the desulfurizing agent layer through inner portion of desulfurizing agent layer.    DESCRIPTION OF DRAWING(S) - The drawing shows a longitudinal cross-sectional view of the desulfurizer. (Drawing includes non-English language text)    Container (1)    Desulfurizing agent layer (2)    Heater (3)    Heat-conducting fin (10)    Control line (CL)