A multifuel fuel cell system includes a hydrogen production unit; at least one fuel cell; means for heating a first catalytic converter element in the hydrogen production unit to an operating temperature which can be preset; means for metering liquid fuel, air, and optionally water to the catalytic converter element to produce a synthetic gas mixture containing hydrogen or a reformate; and means for passing the synthetic gas or reformate to further components of the hydrogen production unit which are connected between the catalytic converter element and the at least one fuel cell. The fuel cell system also contains means for switching the fuel cell system between a first and a second operating mode. Separation occurs between the hydrogen production unit and the at least one fuel cell during the first operating mode, and a communicating connection occurs between the hydrogen production unit and the at least one fuel cell during the second operating mode, so that reformate can be transferred from the hydrogen production unit to the at least one fuel cell only during the second operating mode.