A method for establishing an association between terminal devices, characterized by, comprising: transmitting, by a first terminal device, information of terminal capabilities to a network device, the information of terminal capabilities being used to indicate that the first terminal device has capabilities of receiving and forwarding data; receiving, by the first terminal device, confirmation information transmitted by the network device and used to confirm that the first terminal device has the capabilities of receiving and forwarding data; and establishing, by the first terminal device, an association with a second terminal device according to the confirmation information; the method further comprises: receiving, by the first terminal device, a cluster identifier, ID, from the network device, the cluster ID being used to temporarily identify a cluster to which the first terminal device pertains, wherein the cluster ID is determined according to identification of the first terminal device; and transmitting, by the first terminal device, the cluster ID to the second terminal device, wherein the cluster ID is used for the second terminal device to determine, before transmitting data to the first terminal device or receiving data from the first terminal device, whether the first terminal device is accessible and resources occupied for the data transmission or reception. transmitting, by a first terminal device, information of terminal capabilities to a network device, the information of terminal capabilities being used to indicate that the first terminal device has capabilities of receiving and forwarding data; receiving, by the first terminal device, confirmation information transmitted by the network device and used to confirm that the first terminal device has the capabilities of receiving and forwarding data; and establishing, by the first terminal device, an association with a second terminal device according to the confirmation information; the method further comprises: receiving, by the first terminal device, a cluster identifier, ID, from the network device, the cluster ID being used to temporarily identify a cluster to which the first terminal device pertains, wherein the cluster ID is determined according to identification of the first terminal device; and transmitting, by the first terminal device, the cluster ID to the second terminal device, wherein the cluster ID is used for the second terminal device to determine, before transmitting data to the first terminal device or receiving data from the first terminal device, whether the first terminal device is accessible and resources occupied for the data transmission or reception. receiving, by the first terminal device, a cluster identifier, ID, from the network device, the cluster ID being used to temporarily identify a cluster to which the first terminal device pertains, wherein the cluster ID is determined according to identification of the first terminal device; and transmitting, by the first terminal device, the cluster ID to the second terminal device, wherein the cluster ID is used for the second terminal device to determine, before transmitting data to the first terminal device or receiving data from the first terminal device, whether the first terminal device is accessible and resources occupied for the data transmission or reception.