Bidirectional video transmission method and device

The invention provides a bidirectional video transmission method and a bidirectional video transmission device. The bidirectional video transmission method is applied to a first communication terminal, and comprises the steps of: establishing a first session from the first communication terminal to a second communication terminal and a second session from the second communication terminal to the first communication terminal; and transmitting a first real-time video stream to the second communication terminal via the first session while receiving a second real-time video stream transmitted by the second communication terminal via the second session. Through extending a Miracast protocol, the first communication terminal and the second communication terminal perform bidirectional standard procedures separately at a capability negotiation stage and a session establishment stage, so as to establish the first session and the second session respectively and then implement the real-time bidirectional video transmiss