In this paper, we propose a new scheme for the geometry coding of three-dimensional (3-D) mesh models using a dual graph. In order to compress the mesh geometry information, we generate a fixed spectral basis using the dual graph derived from the mesh topology. After we partition a 3-D mesh model into several independent submeshes to reduce coding complexity, each submesh geometry is projected onto the generated orthonormal basis for the spectral coding. We encode two initial vertices and the dual graph information of the mesh geometry and prove the reversibility between the dual graph and the mesh geometry. The proposed scheme overcomes difficulty of generating a fixed spectral basis, and it provides multi-resolution representation of 3-D mesh models.