A fuel cell system includes fuel cell, electrical storage device that stores electric power generated by the fuel cell, and control device of the fuel cell, the control device performs first control which causes the fuel cell to generate power and increases charging rate of the electrical storage device and second control which restricts output of the fuel cell to be smaller than that in the first control and decreases charging rate of the electrical storage device, and when switching condition, in which electric power demand from the external devices becomes greater than predetermined electric power or state in which electric power demand from the external devices is greater than the predetermined electric power continues for predetermined time, is satisfied, the control device increases power output by the fuel cell during the first control being performed to be larger than that before the switching condition was satisfied.