A new airfoil design method was developed to improve the performance at transonic high lift condition. The main concept of the method is based on the relation between pressure difference across the shock wave and criteria for boundary-layer separation, and an inverse method is also incorporated to realize the designed pressure distribution. An airfoil was designed using this method for transonic transport wing to realize the transonic high lift performance. In this report the application of new airfoil designed here using new transonic method 3-D wing design was conducted.