Message transmission system and message transmission method of OpenFlow protocol network

The invention provides a message transmission system and a message transmission method of an OpenFlow protocol network. The message transmission method comprises the following steps: sending into a first OpenFlow message of a switch to extend a request item in a controller, wherein a compressed encoding mode is declared in the request item, and the message content of the first OpenFlow message is compressed in the compressed encoding mode; sending back into a second OpenFlow message of the controller in the switch to extend a response item, wherein the compressed encoding mode declared by the request item is recorded in the response item, and the message content of the second OpenFlow message is decompressed in a decompressed encoding mode corresponding to the compressed encoding mode. A transmission message is compressed, so that the size of the message is greatly reduced, the blockage is avoided, and the performance is greatly improved.