The present study numerically investigates the aerodynamic characteristics of two-dimensional wings in the vicinity of the ground by solving two-dimensional steady incompressible Navier-Stokes equations with the turbulence closure model of the realizable k −ε model. Numerical simulations are performed at a wide range of the normalized ground clearance by the chord length ( 0.1 ≤ h / C ≤ 1.25 ) for the angles of attack ( 0° ≤α ≤10° ) in the prestall regime at a Reynolds number ( Re ) of 2×106 based on free stream velocity U∞ and the chord length. As the physical model of this study, a cambered airfoil of NACA 4406 has been selected by a performance test for various airfoils. The maximum lift-to-drag ratio is achieved at α = 4° and h / C = 0.1 . Under the conditions of α = 4° and h / C = 0.1 , the effect of the Reynolds number on the aerodynamic characteristics of NACA 4406 is investigated in the range of 2×105 ≤ Re≤ 2×109. As Re increases, l C and d C augments and decreases, respectively, and the lift-todrag ratio increases linearly.