Abstract: On the basis of st ructural similarity and equal stiffness , a scaling-down wing-box and a wing model forflutter test s were designed based on the original metal models. A design method based on design element s for composite st ructures was proposed and a sof tware was developed for scaling-down st ructures and composite st ructuredesign. The models were manufactured with low modulus composite materials and the modal analysis and test s weremade. The result s of analysis are in good agreement with those of the test s. The design method is very practical inengineering and the model with frame-skin st ructure , which realizes the st ructural and dynamic similarities , is muchbetter than the t raditional one , which is of beam²holding appearance st ructure.