FUEL CELL SYSTEM

The present invention relates to a membrane humidifier for a fuel cell capable of simplifying a fuel cell system and miniaturizing the fuel cell system by performing humidification by moisture exchange and cooling by heat exchange in one membrane humidifier, and a fuel cell system comprising same. The membrane humidifier for a fuel cell of the present invention comprises both a humidification module and a heat exchange module in a housing part, and distributes a first fluid to the humidification module and the heat exchange module at a variable distribution ratio.