Abstract: According to the current research situation of closure problem for tailings pond，digital closure design based on 3D points cloud was put forward.Combined with the actual closure needs of one tailings pond，first of all，the three-dimensional points cloud data of tailings pond and surrounding environment was obtained by the long range 3D laser scanner.Then，three-dimensional entity model was generated after the denoising，splicing and modeling process of three-dimensional points cloud data were finished.On the basis of the proposed closure scheme，3D digital design of the drainage system，roof structure of pond，and flood intercepting trench were carried out one by one.The terrace bench as a new roof structure of pond was proposed for the closure design.The flood water on the roof of pond was so easily drained out that the tailings dam can maintain the natural stability,and can greatly reduce the dam break risk from the flood overtopping.Finally，in order to verify the closure scheme，the analysis of flood regulating calculation and stability were implemented.The verification results showed that both met the safety requirements of tailings pond.The accurate data for digital closure design was provided by the entity model established based on 3D points cloud data.Combined with the new roof structure of pond proposed，it can be a new way for closure design of similar tailings pond.

Key words: 3D points cloud, Digital closure design, Roof structure of pond, Terrace bench