NCREE has originally developed 5D digital space—on the basis of 3D city models and connections of different kinds of sensors around the world—is an online to offline virtual space with a combination of rising 5G technology advantages. Collecting and reorganizing various 3D cartographic data with Building Information Modeling (BIM), satellite imagery, UAV 3D modeling with high-resolution cameras, LiDar point cloud data, etc., can increase the diversity of the building and landscape to make the city more realistic. 5D+5G smart city platform speeds up all aspects of value-add applications of smart cities, including Intelligent Transportation System (ITS), Smart Energy (SE), and Ambient Intelligent (AmI). We expect that the 5D smart city becomes the digital twin of a real city.