The invention discloses a water supply device allowing automatic air discharging. The water supply device includes a frame, an air release valve, a motor case, an operation panel, wires, an adjustmentvalve, a barrel body, a water inlet, a water storage device, a pipe, and a supporting column; the frame is of a clip-shaped structure, the height of the frame is 4 cm, the length of the frame is 90 cm, and the width of the frame is 30 cm; the frame and the water storage device are movably connected through an interference fit manner; the water storage device is of a cylindrical structure, the height of the water storage device is 75 cm, and the radius of the water storage device is 12 cm. The water supply device allowing automatic air discharging has the air release valve, can suck air in thebarrel body out through a piston rod of the air release valve and a hydraulic cylinder, can discharge air via a discharging opening, can avoid the situation that water is sprayed out and lots of water is lost due to mutual extrusion of the water flow and the air, and can ensure normal water supply to the barrel body.