Abstract: For fast surface reconstruction from given scattered point clouds,this paper presents a two-level implicit function interpolation algorithm based on compactly supported radial basis function(CSRBF).Firstly,a threshold for center reduction is set before interpolation,so the center points of CSRBF are reduced and the linear system based on CSRBF is simplified.Secondly,the point cloud model is approximated by interpolating in the coarse scale.Then,the surface is fitted in the fine scale and it sums up the coarse surface and the fine surface.Finally,a regularization parameter is introduced to regularize the CSRBF matrix to deal with the noise of 3D point cloud models.Experimental results show that this algorithm can not only easily process the 3D scattered datasets with noise,but also achieve rapid surface reconstruction.The final surface models are smooth and realistic.