Multi-LNG tank container synchronous filling system and filling method

The invention relates to the field of LNG transportation, in particular to a synchronous filling system and method for multiple LNG tank containers. The synchronous filling system comprises a mounting platform, a storage tank and a main pipe are mounted on the mounting platform, and an input pipe is arranged on the storage tank; the synchronous filling system further comprises a butt joint device, a butt joint buffering structure and a tank body buffering structure. The butt-joint buffering mechanism further comprises a mounting frame, a fixing block and a butt-joint plate, the mounting frame is mounted on the mounting platform and connected with the fixing block, the butt-joint plate is slidably mounted on the mounting frame and slidably matched with the fixing block, and the butt-joint device is mounted on the butt-joint block and used for connecting the input pipe and the main pipe; and the tank body buffer structure is mounted on the mounting platform and is used for supporting the storage tank. The funct