Fuel Cell System

A fuel cell system, comprising:

• a fuel cell having a fuel gas flow path and an oxidant gas flow path and generating electricity by being supplied a fuel gas to the fuel gas flow path and an oxidant gas to the oxidant gas flow path;
• fuel gas supplying means for supplying the fuel gas to the fuel gas flow path;
• a discharge valve for discharging a gas in the fuel gas flow path outside;
• fuel gas exchange means for exchanging an atmosphere inside the fuel gas flow path for the fuel gas at a starting of the system by opening the discharge valve, while supplying the fuel gas to the fuel gas flow path from the fuel gas supplying means;
• and
• cold start determination means for determining whether to conduct or not to conduct the cold start of the system,
• wherein when the cold start determination means determines to conduct the cold start, the cold start determination means increases a total discharge amount of a gas to be discharged by opening the discharge valve for exchanging the atmosphere inside the fuel gas flow path for the fuel gas, thereby increasing a fuel gas concentration in the fuel gas flow path.