A method, an apparatus, and a system for implementing private network traversal are disclosed, where a message exchanged between a TURN server in a public network and a communications terminal in a local area network is transmitted through a pre-established websocket connection. The method includes: receiving, by the TURN server, a resource allocate request sent by the communications terminal, allocating a relay address and a resource port for the communications terminal; receiving a TURN data packet sent by the communications terminal, where the TURN data packet includes communication data and a multiplexing identifier, and sending the communication data to the remote node through the communications channel identified by the multiplexing identifier, thereby solving a problem in an existing TURN technology that in case that a firewall only opening an HTTP port is deployed, communication between a communications terminal in a local area network and a remote node cannot be implemented.