For the complex modern aircraft wing structures, a detailed finite element structural modeling requires a large amount of modeling time and cost, and there are many difficulties and know-how to construct accurate analysis model. In addition, it often gives impractical results for the free vibration analysis, since the results include many trivial local modes. Specially, the detailed three-dimensional modeling is nearly impossible in preliminary design stage because of insufficient structural information and various design changes. Therefore, it is necessary and very useful to use efficient equivalent model of complex aircraft structures in the aeroelastic analysis. Actually, the equivalent model can be obtained rapidly, if we have structural test data and ground vibration test data of a real structure, because the modification of equivalent model is very simple. In this study, therefore, the efficient equivalent modeling methods of wing structure are presented and validated. Using the equivalent model, free vibration analysis and transonic flutter analysis are performed for the K100-04 middle-type commercial aircraft wing.