FUEL CELL SYSTEM

A fuel cell system wherein, at the time of activating the fuel cell system, the controller determines whether or not the temperature of the fuel cell detected by the temperature sensor is equal to or less than a temperature corresponding to activation at sub-zero temperatures, and wherein, when the controller determines that the temperature of the fuel cell detected by the temperature sensor is equal to or less than the temperature corresponding to the activation at sub-zero temperatures, the controller sends a command to the fuel gas supplier to supply the fuel gas to the fuel cell, and the controller controls rotation of the circulation pump to stop a flow of the fuel off-gas in the circulation flow path.