Abstract: An energy-saving operation and control method for a UPS. The method includes performing a concomitant detection on a self-discharge condition of the UPS without any further processing before the concomitant detection, to obtain an automatic discharging amount per unit of time when the battery is in an un-operating state; determining a replacement timing among three kinds according to a value of the discharging amount; and generating a replacement signal at a corresponding time point according to the replacement timing; according to the generated replacement signal, performing a process of power charging and power discharging on the battery.