A method for providing a relay service, applied to a mobility management entity, MME, comprising: receiving a first message sent by relay user equipment, UE, wherein the first message is used to request to provide a relay service to remote UE, and the first message comprises a globally unique temporary identity, GUTI, of the remote UE; obtaining (S202, S503, S504, S506) a first identifier of the remote UE according to the GUTI of the remote UE, wherein the obtaining (S202, S503, S504, S506) the first identifier comprises obtaining (S503, S504, S506) context information of the remote UE according to the GUTI of the remote UE, and obtaining the first identifier of the remote UE from the context information of the remote UE; and sending (S203, S508) a second message to a packet data network-gateway, P-GW, wherein the second message comprises the first identifier of the remote UE; characterized in that the method further comprises: receiving (S204, S510) a third message sent by the P-GW, wherein the third message comprises an uplink traffic flow template,TFT, the uplink TFT comprises an uplink packet filter of the remote UE, and the uplink packet filter of the remote UE is used by the relay UE to map an uplink data packet of the remote UE to an evolved packet data, EPS, bearer of the relay UE; and sending (S205, S511) a fourth message to the relay UE, wherein the fourth message comprises the uplink TFT; wherein the first identifier of the remote UE comprises: an international mobile subscriber identity IMSI of the remote UE or an Internet Protocol,IP, address of the remote UE; wherein the third message further comprises a first TFT, the first TFT is used by the relay UE to route a downlink data packet of the remote UE to a bearer on a PC5, and the PC5 is an interface between the relay UE and the remote UE; and the fourth message further comprises the first TFT. receiving a first message sent by relay user equipment, UE, wherein the first message is used to request to provide a relay service to remote UE, and the first message comprises a globally unique temporary identity, GUTI, of the remote UE; obtaining (S202, S503, S504, S506) a first identifier of the remote UE according to the GUTI of the remote UE, wherein the obtaining (S202, S503, S504, S506) the first identifier comprises obtaining (S503, S504, S506) context information of the remote UE according to the GUTI of the remote UE, and obtaining the first identifier of the remote UE from the context information of the remote UE; and sending (S203, S508) a second message to a packet data network-gateway, P-GW, wherein the second message comprises the first identifier of the remote UE; characterized in that the method further comprises: receiving (S204, S510) a third message sent by the P-GW, wherein the third message comprises an uplink traffic flow template,TFT, the uplink TFT comprises an uplink packet filter of the remote UE, and the uplink packet filter of the remote UE is used by the relay UE to map an uplink data packet of the remote UE to an evolved packet data, EPS, bearer of the relay UE; and sending (S205, S511) a fourth message to the relay UE, wherein the fourth message comprises the uplink TFT; wherein the first identifier of the remote UE comprises: an international mobile subscriber identity IMSI of the remote UE or an Internet Protocol,IP, address of the remote UE; wherein the third message further comprises a first TFT, the first TFT is used by the relay UE to route a downlink data packet of the remote UE to a bearer on a PC5, and the PC5 is an interface between the relay UE and the remote UE; and the fourth message further comprises the first TFT. receiving (S204, S510) a third message sent by the P-GW, wherein the third message comprises an uplink traffic flow template,TFT, the uplink TFT comprises an uplink packet filter of the remote UE, and the uplink packet filter of the remote UE is used by the relay UE to map an uplink data packet of the remote UE to an evolved packet data, EPS, bearer of the relay UE; and sending (S205, S511) a fourth message to the relay UE, wherein the fourth message comprises the uplink TFT; wherein the first identifier of the remote UE comprises: an international mobile subscriber identity IMSI of the remote UE or an Internet Protocol,IP, address of the remote UE; wherein the third message further comprises a first TFT, the first TFT is used by the relay UE to route a downlink data packet of the remote UE to a bearer on a PC5, and the PC5 is an interface between the relay UE and the remote UE; and the fourth message further comprises the first TFT.