The utility model discloses a large axial flow fan impeller with wing flaps. The large axial flow fan impeller with the wing flaps comprises a wheel hub and blades, wherein the blades are uniformly distributed at the periphery of the wheel hub; the wing flaps are arranged at the leeward end of the root of one side of each blade; the inner ends of the wing flaps are fixedly connected with the wheel hub; the wing flaps are arc-shaped square plates; the upper surfaces of the wing flaps are formed by extending along arc transition of the upper surfaces of the leeward ends of the blades; the lower surfaces of the wing flaps are arc-shaped and in arc transition connection with the lower surfaces at the leeward ends of the blades, thereby facilitating the increase of the lifting areas of the roots of the blades, greatly increasing linear speeds of the blades at the root of the impeller, improving the working efficiency of the impeller and achieving the effect of saving energy consumption.