The utility model discloses a low voltage power-off monitoring terminal for monitoring a three-phase voltage power-down situation of a distribution line to remind a far-end master station system of power-down information. The low voltage power-off monitoring terminal comprises a power supply for obtaining the phase voltage of the distribution line and providing operating voltage for a functional plate of the low voltage power-off monitoring terminal, and a power supply management circuit installed between the power supply and the functional plate and used for controlling the power supply to charge and discharge the functional plate. The power supply management circuit is composed of a super capacitor C1, a constant current charging circuit S1 and a switching transistor D1. When the distribution line at a zone area is power on and power down, the super capacitor C1 conducts charging and discharging respectively to support the operating power supply of the functional plate, a constant current charging current is provided to the super capacitor C1 through the constant current charging circuit S1, and the generation of a current circulating loop is prevented through the switching transistor D1.