Disclosed are a method and a system for transmitting a file folder from the sending end to the receiving end. The system uses a file folder transmission unit at the sending end side to generate a directory structure file of the file folder. The directory structure file may have properties such as the size of the file folder, paths and path lengths of the files in the file folder. The sending end then sends the directory structure file to the receiving end through the file folder transmission unit to allow the system to determine which files in the file folder need to be transmitted. The needed files in the file folder are then transmitted to the receiving end according to the determination. The sending end and the receiving end may communicate using an instant messaging tool. The disclosed method and system allow a faster and more convenient file folder network transmission.