An alkaline fuel cell having an electrolyte, and anode and cathode
electrodes disposed on two sides of the electrolyte is provided. A fuel
cell system has this fuel cell, a discharge passageway that is connected
to a discharge opening of the fuel cell and that discharges from the fuel
cell an exhaust fuel containing unreacted fuel, and a circulation
passageway that is connected to an introduction opening for introducing
the fuel into the fuel cell and that circulates and supplies the exhaust
fuel to the fuel cell. The fuel cell system further includes fuel/water
separation means linked to the discharge passageway and the circulation
passageway and disposed between the discharge and circulation
passageways. The means separates and removes water from the exhaust fuel
flowing in from the discharge passageway, and then causes a concentrated
fuel from which water has been separated and removed to flow into the
circulation passageway.