Abstract: The propeller slipstream will change the effective angle of attack and air velocity of the airplane wing, affecting the aerodynamic characteristics of the whole airplane. Compared with wing-mounted propeller airplane, the relative position relationship between propeller and wing of single-engine propeller airplane is flexible and changeable. In order to study the influence of slipstream of single-engine propeller airplane with different aerodynamic layouts on the wing, this paper studies the influence of slipstream on light single-engine low- and high-wing propeller airplanes by force-measuring wind tunnel tests. The results verify that the simple plugging of the nose air inlet of the test model will produce considerable additional drag due to the propeller slipstream; the additional drag is proportional to the propeller thrust coefficient but independent of the flap deflection. Propeller slipstream increases the lift curve slope, maximum lift, drag and pitching moment, but somewhat reduces the lift-to-drag ratio and longitudinal stability. The relative position between the nose propeller and the wing significantly affects the stall angle of attack. Propeller slipstream increases the stall angle of attack for single-engine high-wing airplanes but decreases that for single-engine low-wing airplanes. The flow visualization and theoretical analyses show that the propeller slipstream moves to the top of the wing of single-engine low-wing airplanes, causing strong upwash flow, increasing the local angle of attack of the wing, resulting in a large flow separation region on the upper surface of the wing, and reducing the airplane stall angle of attack.