To record the information of scene of accident is the respnsibility of the Accident Investigation Agency. In order to improve the quality and scale of recorded information. This study apply the concept of reverse engineering, comparesing the quality of point cloud obtained from different optical scanners. by evaluating different instruments with multiple criteria including the density of point cloud, precision, scanning speed, and portabiliy, this study choose the most suitable instrument for accident scene investigation. Also, this study obtain point cloud with these instruments, and use it to reconstruct CAD model. Finally, case studies regarding CAD model reconstructions are presented.