Insect-mimicking flapping-wing micro air vehicles (FWMAVs) have attracted substantial interest in recent years due to a variety of potential civilian and military applications. Insect wings may be strongly deformed during flight, and their structures are generally anisotropic because of the combination of membranes and tapered veins. Hence, modeling the insect wing is an important and complex task. In this paper, we propose a body-spring system of an insect wing structure. For validation, modal analysis is performed, and the natural modes and frequencies are compared with those from an experiment and a finite element model. The results of the first two modes of the structure show good agreement. The proposed model can be coupled with aerodynamic codes to study the dynamics of FWMAVs.