An electrical storage system includes: an electrical storage device (10) including serially connected electrical storage blocks; a relay (SMR-B, SMR-G) switching a connection state between the electrical storage device and a load; a controller (30, 34) controlling the relay; and a current interruption circuit (60) interrupting energization of the electrical storage device. The current interruption circuit (60) includes an alarm circuit (63) outputting an alarm signal indicating that any one electrical storage block is overcharged or overdischarged by comparing a voltage value of each electrical storage block with a threshold; a latch circuit (64) retaining the alarm signal; and a transistor (68) causing the relay to switch from an on state to an off state upon reception of a latch circuit output signal. The controller determines an energization state of the electrical storage device after executing control for causing the alarm circuit to output the alarm signal by changing the voltage value or the threshold.