The invention provides a water-saving type water feeding and discharging valve on a pedestal pan. According to the water-saving type water feeding and discharging valve, a water supplementing pipe at the upper part of a water feeding valve is connected onto a water overflowing pipe at one side of a water discharging valve; the bottom of the water overflowing pipe is communicated with the bottom of the water discharging valve; an end opening of the water overflowing pipe is buckled with an end cover of the water overflowing pipe; the end cover of the water overflowing pipe is provided with a water supplementing pipe connector; the water supplementing pipe at the upper part of the water feeding valve is connected onto an upper end opening of the water supplementing pipe connector; a transverse rod is hinged below the end cover of the water overflowing pipe; the front-end head of the transverse rod is adapted to the lower end opening of the water supplementing pipe connector; a water overflowing pipe floating barrel is hung at the rear end of the transverse rod through a hanging rod; when the water overflowing pipe floating barrel moves upwards, the lower end opening of the water supplementing pipe connector is at an opened state; when the water overflowing pipe floating barrel moves downwards, the lower end opening of the water supplementing pipe connector is at a closed state. According to the water-saving type water feeding and discharging valve, water supplementation in the water overflowing pipe is carried out along one part of progresses before water feeding is stopped; the position, namely the up-down position of the water overflowing pipe floating barrel in a water tank, of the hanging rod on a slide sleeve is set, so that the requirements of a water-inlet water level and water amount needed by siphon can be met and water resources can be saved.