This study analyzed the aerodynamic characteristics of bang-pae kite, a kind of Korean traditional kites with rectangular shape and a wind hole in the center. In order to analyze the aerodynamic characteristics, wind tunnel test was performed and aerodynamic data were also measured by using a pyramidal balance as radius of wind hole and aspect ratio. The results show that lift and drag decreases as the radius of wind hole grows. However, stability was increased because lift coefficient was reduced slowly after stall. The length of gong-su sting in flying wing was calculated by using the aerodynamic data from these experiments. The calculated values almost matched with gong-su string length handed down by Korean ancestors.