The invention discloses a repair system for improving the capacity by storage battery pulse shallow discharge maintenance. The repair system comprises: a main controller, a charging module, a selection switch and a shell, wherein the selection switch is arranged outside the shell, and is set to have n gears; the signal ends of the various gears are connected with the control module, and n is a positive integer; the control end of the charging module is connected with the control module; during use, an output wire of the charging module is connected to two ends of a lead storage battery; the main controller controls a repair charging process of the lead storage battery through the selection switch; and in a charging process, at least two sections of current having different intensities areset. According to the repair system, a discharging module can be added; the control end of the discharging module is connected with the control module; and during use, an output wire of the discharging module is connected to two ends of the lead storage battery. The repair system realizes rated electrical quantity charging for repairing of the lead storage battery by selecting the gears of the selection switch. The invention also discloses a repair method for improving the capacity by storage battery pulse shallow discharge maintenance.