A power storage system mounted on a vehicle including: a power storage device (10) that performs charging and discharging; a voltage monitoring unit (20) that detects a voltage of the power storage device (10); and a controller (50) that controls charging and discharging of the power storage device (10), wherein the controller (50) performs consistency determination processing, which determines whether the controller (50) and the voltage monitoring unit (20) are consistent, based on control information that is predefined for the power storage device (10) for which the controller (50) controls charging and discharging and, if it is determined in the consistency determination processing that the controller (50) and the voltage monitoring unit (20) are not consistent, performs control so that the power storage device (10) does not perform charging and discharging.