The present invention provides a quasi-elliptical airfoil for a high-speed helicopter rotor reflux region. The airfoil is a blunt trailing edge airfoil with symmetrical front and rear. The leading edge radius of the upper surface of the airfoil is 0.0385, the leading edge radius of the lower surface of the airfoil is 0.0230, the trailing edge radius of the upper surface of the airfoil is 0.0385, and the trailing edge radius of the lower surface of the airfoil is 0.0230. The maximum thickness of the airfoil is 26% C, the maximum thickness is 50% C and the curvature is 2.8% C. The lower surfaceof the airfoil has some concavity near the leading edge and the trailing edge, so that the lift of the airfoil is improved. The invention has the advantages that the quasi-elliptical airfoil applied to the rotor reflux region of a high-speed helicopter designed according to the actual flow characteristics of the reflux region has smaller resistance of the reflux region, higher aerodynamic efficiency and can effectively suppress the flow separation phenomenon, thereby improving the cruise efficiency of the helicopter and meeting the requirements of a new generation of high-speed helicopter.