The invention discloses a streaming data server, which comprises a data receiving module, a preprocessing module, a standard data output module and a data pool, wherein the data receiving module is used for acquiring streaming data from data acquisition equipment, caching the acquired streaming data into a receiving buffer, and starting the preprocessing module after the streaming data is cached; the preprocessing module is used for converting the streaming data cached in the receiving buffer into a binary data stream, and writing the binary data stream into the data pool in a queue data structure; and the standard data output module is used for sequentially outputting the valid queue header data of the binary data stream in the data pool through an object linking and embedding for process control (OPC) standard interface. The invention also discloses a streaming data transmission method and a data transmission system. By the streaming data server, the streaming data transmission method and the data transmission system, the streaming data such as text data, image data and the like can be conveniently transmitted to a client, the unified access of the data can be realized, and remote bandwidth resources and field processing resources can be saved.