A relay replacement method, for switching to a new relay when a relay needs to be replaced in a process of communication between a first terminal and a second terminal by means of a source relay, comprising: a second terminal receives measurement reports sent by other relays; the second terminal determines, according to the measurement reports, a destination relay; the second terminal sends change request information to the destination relay, the change request information comprising internet protocol (IP) addresses of a first terminal and the second terminal; the second terminal receives an IP address, sent by the destination relay, of the destination relay; and the second terminal sends the IP address of the destination relay and a layer-2 address to the first terminal by means of a source relay. Thus, a second terminal and a first terminal can continuously communicate by means of a destination relay, thereby achieving the continuity of network data transmission and improving the network performance.