A fuel cell system according to the present invention has a movement drive device (load) (2), a fuel cell (10) for supplying electric power to the drive device, an electric power storing device (31) consuming electric power equivalent to the consumption power of the drive device, and an electronic control unit (connection control unit) (4) for controlling the connection of the fuel cell to the drive device. Before the fuel cell is connected to the drive device by the control of the electronic control unit, the fuel cell is made to generate electric power equivalent to the consumption power of the drive device, and the generated power is supplied to the electric power storing device. When a fuel cell voltage at the time of supply of the electric power to the electric power storing device is not less than a specified value, the connection between the fuel cell and the drive device is permitted.