An electrical storage system includes a relay switching between an on state where an electrical storage device (10) is connected to a load and an off state where connection of the electrical storage device with the load is interrupted; a controller controlling an on-off state of the relay; and a current interruption circuit (60) interrupting energization of the electrical storage device. The current interruption circuit includes an alarm circuit (63) outputting an alarm signal indicating that any one electrical storage block is in an overcharged state by comparing a voltage value of each electrical storage block with a threshold; a latch circuit (64) retaining the alarm signal; a transistor (66) causing the relay to switch from the on state to the off state upon reception of an output signal of the latch circuit; and a power supply circuit (63d) generating electric power for operating the latch circuit using electric power of the electrical storage device.