The invention relates to a three-dimensional file format system and a reading method. The three-dimensional file format system comprises a file header module, a Node information module and a user-defined information module, and is characterized in that the file header module is used for storing file marks, version numbers and basic information of the user-defined information module; the Node information module is used for storing ordered tree structures of formatted files, node names, node layers and connection relations between nodes; and the user-defined information module is used for storing model structure information, texture information, animation effect information, map information, light source information and view angle information. According to the format, classification processing is firstly performed on the same data in three-dimensional model files, then compression processing is performed on each category of data respectively to obtain compressed information blocks, the information blocks are arranged according to an ordered tree structure, so that a circumstance of data confusion can be prevented, the space occupied by the files is significantly reduced, and the compression effect is improved by nearly 10 times compared with the existing obj format.