Raw fuel vaporizing apparatus and fuel cell system equipped with raw fuel vaporizing apparatus

A raw fuel vaporizing apparatus comprising: a vaporizer (12) for vaporizing liquid raw fuel; a raw fuel introducing device for introducing the liquid raw fuel into the vaporizer; a catalyst combustor (11) into which fuel and air are supplied for catalytic combustion, the catalyst combustor generating heat in the presence of a catalyst and supplying the resulting heat to the vaporizer to vaporize the liquid raw fuel; a fuel introducing device for introducing the fuel into the catalyst combustor; an air introducing device for introducing the amount of the air suitable for catalytic combustion into the catalyst combustor; a heat transferring gas introducing device introducing heat transferring gas into the catalyst combustor to transfer heat retained by the catalyst combustor to the vaporizer; and a controller increasing the amount of the heat transferring gas through the heat transferring gas introducing device when the amount of vapor generated in the vaporizer is increased.