The fuel cell system includes a fuel cell stack, a fuel supply supplying a fuel to the fuel cell stack, and an oxidizing agent supply supplying an oxidizing agent to the fuel cell stack. The fuel cell stack includes a first end plate, a moisture exchanger, an electrical generator, and a second end plate. The moisture exchanger includes a first area where a dried supply oxidizing agent flows, a second area where a humid emission fuel flows, and a third area where a humid emission oxidizing agent flows, and the first area exchanges moisture with the second and third areas using a moisture exchange layer.