The present invention provides a method for establishing an interface and communication between a relay node (RN) and a core network. The method may include: a base station sends an IP address and an identification of a control plane node of the core network to an RN; the base station sends an IP address and an identification of the RN to the control plane node of the core network; the RN and the node communicate with each other by using information of each other received from the base station. The method according to the present invention realizes transparent transmission of access layer signaling between a relay node and a core network via a base station, which reduces complexity of the process when the RN is in movements, makes it easier to support multiple access techniques, and reduces the complexity in network configurations.