A top-suspended centrifuge drum was studied with consideration of fluid-structure interaction of the drum and massecuite. The analytical dynamic model was built by finite element method, and a triangle plate element was used to build the basket wall. Moreover, the triangular prism element of six nodes was also utilized to build the massecuite. Therefore, the natural frequencies with and without consideration of fluid-structure interaction and the natural frequencies were obtained respectively. The results showed that the natural frequencies with consideration of fluid-structure interaction were smaller than that without this consideration.