Fuel cell system

A fuel cell system with an idle stop function in which electric power generation by a fuel cell can be stopped temporarily, the fuel cell system comprising:

• a cathode pressure control unit configured to control a pressure of a cathode gas to be supplied to the fuel cell on the basis of a load of the fuel cell;
• and
• an anode pressure control unit configured to control a pressure of an anode gas to be supplied to the fuel cell to become higher than the pressure of the cathode gas so that a differential pressure between the pressure of the anode gas and the pressure of the cathode gas becomes a predetermined differential pressure or lower,
• wherein the anode pressure control unit controls the pressure of the anode gas to be supplied to the fuel cell to be a recovery-time pressure or lower at a time of recovery from idle stop, and prohibits reduction of the pressure of the anode gas or regulates a reduction width, the recovery-time pressure being obtained by adding the predetermined differential pressure to a predetermined pressure equivalent to an atmosphere pressure.