Based on some research and comparison of a variety of interpolation methods, two kinds of interpolation methods were analyzed on the principle and programmed in this article, including the shape function weighted area coordinates as well as surface spline interpolation method, which is applied for the coupling calculation of force and displacement between the aerodynamics and structure in 3d space respectively. The interpolation for the aircraft model is conducted with these two kinds of methods. In the end, the reasonability is confirmed by comparing the results before and after interpolation.