The invention provides a remote maintenance device of an uninterruptible power supply. The device comprises a voltage acquiring loop, a switching signal acquiring loop and a remote control loop; three ports are introduced from the voltage acquiring loop; an AC power supply supplies power to the remote control loop; a first relay and a second relay are connected in parallel between a positive electrode and a negative electrode of the AC power supply, wherein the relays are respectively connected in series with normally-opened contacts of a third relay and a fourth relay; the normally-opened contact of the third relay is connected in parallel with a third normally-opened contact of the first relay; one of the ends of the third relay and the fourth relay is connected with the negative electrode of a DC power supply, and a fourth port and a fifth port are respectively introduced from the other one of the ends of the third relay and the fourth relay; the tenth port and an eleventh port are respectively introduced from the positive electrode of the DC power supply; a normally-closed contact of the second relay is connected in series with the first relay; an eighth port and a ninth port are introduced from the second normally-opened contact of the first relay; the switching signal acquiring loop comprises a first normally-closed contact of the first relay; a sixth port and a seventh port are introduced from the contact. With the adoption of the device, the voltage value and working state of a storage battery can be monitored, and the storage battery can be remotely controlled to charge and discharge.