Abstract: Air defence fortificationsis is long and the internal environment is complex. Three dimensional laser scanning technology has broken through the limitations of traditional single point precise measurement. 3D laser scanning can measure the three dimensional coordinate in large area, and break through the limitations of traditional single point precise measurement. It has the advantages of continuous, fast, non-contact, automatic and all-weather work. The article takes a section of air defence fortifications as an example, studies the work flow of 3D laser scanning, makes model reconstruction and surveying and mapping based on point cloud data, completes the analysis and evaluation of the quality of the point cloud.

Key words: 3D laser scanning technology, model reconstruction, surveying and mapping, air defence fortifications