A fuel cell system includes a fuel cell stack, a fluid unit including a heat exchanger for heating an oxygen-containing gas, before the oxygen-containing gas is supplied to the fuel cell stack, and a casing for containing the fuel cell stack and the fluid unit. A first output terminal is electrically connected to one electrode, and provided adjacent to an end plate. A second output terminal is electrically connected to another electrode through a tightening member, and provided adjacent to the end plate. The fluid unit is provided adjacent to an end plate.