Message transmission method and device

The invention provides a message transmission method, which is applied to a first device, the first device comprises a transmission layer and a transaction layer, and the method comprises the following steps: the first device receives a message to be sent to a first application of a second device; the first device determines whether a transmission layer TP connection is established between the transmission layer of the first device and the transmission layer of the second device; when at least one TP connection is established between the transmission layer of the first equipment and the transmission layer of the second equipment, the first equipment determines that the at least one TP connection is used for transmitting the message of the first application, and the at least one TP connection is the TP connection established by the first equipment for transmitting the message of the second application. Through the message transmission method, the messages of different applications can be transmitted through the same TP connection, and reliable connections do not need to be established for different applications respectively, so that the resource overhead required for establishing the connection can be reduced.