According to the whole technological demands and takeoff and landing demands for high lift devices on large aircrafts, this article summarizes a process of how to design high lift devices and presents an integrated design idea connecting aerodynamics and mechanism design. By use of the secondary development of CATIA, a set of aero-mechanism integrated design platform is established, which provides users takeoff/landing configurations of high lift devices with the inputs of design parameters as well as supporting systems. Finally using efficient aerodynamic evaluation measures judges whether the takeoff/landing performance of high lift devices under the guidance of the mechanisms meet the requirements of the overall design.