Abstract: A novel approach is presented for precise registration of range images with a new error metric, based on the inter-space between overlap regions.The proposed method aligns range images using the surface mean inter-space measure （SMISM）.This measure takes on the mean3D inter-space associated with each valid triangle-pair in the overlap region as the error metric to guide the range image registration.And then the centroids of corresponding triangles are employed as point-pairs to calculate the new transformation.Experimental results demonstrate that the presented method is insensitive to noises and has high precision as well as a nice performance on convergence.