Abstract:In this paper, the concept of space-mesh-surface distance is introduced. Base d on the space-mesh-surface distance, two kinds of interpolation surfaces defi ned on space-mesh-surface of triangulation are constructed. They are space-me sh-surface distance based radial basis function interpolation surface and Krigi ng interpolation surface. The infinite smoothness of the surface is discussed fo r those points that have unique distance path on space-mesh-surface. An algori thm for computing space-mesh-surface distance, named broken line tracing metho d, is given. As a whole interpolation surface, they are well in consistence with the space-mesh-surface in shapes and are suitable to be applied in local shap e estimation, such as gradient and direction estimations.