An electric storage system includes plural electric storage elements, a voltage detection circuit, a discharging circuit, and a controller. The controller is configured to: (a) control an operation of the discharging circuit on the basis of the voltage values detected by the voltage detecting circuit, (b) determine a first reference voltage value indicating a lowest voltage value from the voltage values of the plurality of electric storage elements, (c) discharge the electric storage element indicating the voltage value of which a voltage difference from the first reference voltage value is greater than a first threshold value, and (d) set the first threshold value to a smaller value as the first reference voltage value becomes lower.