3D laser scanning is another technology revolution in acquiring the geographic data after GPS technology and terrestrial 3D laser scanner takes the advantages of high resolution and efficiency in acquiring topographic information.Firstly,its applicability to this kind of terrain and condition is discussed.Then methods of DEM surface reconstruction from its cloud data are put forward and the whole modeling process are accomplished using Trimble GX200 3D laser scanner.Modeling accuracy is analyzed afterwards and finally comes to a conclusion that DEM fromterrestrial 3D laser scanning has a great value in precision engineering survey.