FUEL CELL SYSTEM

When it is judged that a fuel cell stack 10 is drying up, recovery control is performed. In recovery control, the cathode pressure control valve 47 is controlled so that the cathode pressure becomes an increased cathode pressure, a discharge flow rate of air of a turbocompressor 44 is set to an increased flow rate of air, and a bypass control valve 41b is controlled so that a flow rate of air which is fed to the fuel cell stack is maintained at the requested flow rate of air. Furthermore, a combination of an increased cathode pressure and increased flow rate of air for making the amount of consumed power of the turbocompressor required for eliminating dry-up the smallest is set based on the requested flow rate of air of the fuel cell stack.