Composite material as an excellent aviation material is widely used due to its high intensity, stiffness and designable performance. Metallic material is more widely used in airframe material because of low cost and excellent range of properties ,which can meet particular requirements and have experience of manufacturing tech鄄 niques. As an example of some type of aircraft, the design procedure of these two schemes of composite and metallic material were analyzed and discussed in detail in this article. It is hopeful to provide technical support for the design on the rear spar of center wing.