Abstract: A brief review about several phases and present status of flexible multibody dynamics was given and the existing modeling methods of rigidflexible coupling dynamics were summarized. Five indexes, including scientific index, general index, identifiable index, compatible index and efficient index, were proposed to evaluate the existed modeling methods. It shows that the existed modeling methods can not satisfy the actual needs of engineering application and new modeling method which satisfies all the evaluating indexes should be investigated. The research targets including modeling theory, computational methods and experiments were suggested for the rigidflexible coupling dynamics of the flexible multibody systems.