Abstract: The spatial relationships and geometry features of line group based on spatial statistical character are described.The conceptual neighborhood network of topological relationships between lines is used to define topology similarity between line groups.The directional mean is applied to define direction similarity between line groups,their circular variance is utilized to define distance similarity between line groups.Combined with the length,average length,density and tortuosity of line group,a computation model for similarity assessment between line groups is established.Experiment results show that the similarity assessment is generally consistent with surface features and intuitive cognition of human.