A method for operating a comprehensive three-dimensional teaching field, including: collecting, by a sensor, a depth data of a real teaching space, point cloud data of a teacher and voice data of the teacher; performing calculation and caching of an architecture for data storage, transmission and rendering of a virtual teaching space based on edge cloud; building a database model of the virtual teaching space by using a R-tree spatial index structure to realize distributed data storage; generating a virtual avatar model updating in real time by positioning and tracking an action of a user; displaying an image of the virtual teaching space on terminals of the teacher and a student through encoding, uploading, 5G rendering and decoding by using a 5G link.