In 3D geodynamics numerical simulation research, it is often required to mesh the whole Earth or part of the spherical shell, and the size of mesh is much more important to our research. Computing meshes not only meet the need of geophysical analysis, but also avoid the computing redundancy caused by too small meshes near the core. In this paper, one structured refining meshing scheme is presented for Earth, which can make all mesh sizes in the Earth more uniform, and refine the meshes near the surface area which geophysical analysis required. And in the simple computing trial for the earth meshes generated by the mesh scheme in this paper, good results are obtained.