A method for performing cellular network relocation, applied to a source evolved Node B, eNB, for relocation, the method comprising: sending, by the source eNB to a target eNB for relocation, a relocation Request, REQ, message configured to instruct the target eNB to execute a primary user-plane function, wherein the relocation REQ message contains context information of User Equipment, UE, on the source eNB (S10); and after receiving a relocation REQ Acknowledgement, ACK, message returned by the target eNB and configured to acknowledge that the target eNB is a primary eNB after relocation, sending, by the source eNB, context information of the primary user-plane function on the source eNB to the target eNB, and stopping executing the primary user-plane function, so that the target eNB executes the primary user-plane function upon receiving the context information of the primary user-plane function from the source eNB, wherein the relocation REQ ACK message contains a user-plane address for the target eNB to receive data packets after relocation (S20); wherein the source eNB is a user-plane primary eNB, and the target eNB is a Secondary eNB, SeNB; the source eNB comprises the secondary user-plane function, and a secondary user-plane function of the source eNB keeps being executed in the relocation process, wherein for an uplink radio bearer, the primary user-plane function comprises: reordering data packets sent from the UE and processed by the secondary user-plane function; and for a downlink radio bearer, the primary user-plane function comprises: numbering data packets from an upper-layer network; and the secondary user-plane function comprises one or more of the following functions: a security function, a Radio Link Control, RLC, protocol stack function, a Media Access Control, MAC, protocol stack function and a Physical, PHY, protocol stack function. sending, by the source eNB to a target eNB for relocation, a relocation Request, REQ, message configured to instruct the target eNB to execute a primary user-plane function, wherein the relocation REQ message contains context information of User Equipment, UE, on the source eNB (S10); and after receiving a relocation REQ Acknowledgement, ACK, message returned by the target eNB and configured to acknowledge that the target eNB is a primary eNB after relocation, sending, by the source eNB, context information of the primary user-plane function on the source eNB to the target eNB, and stopping executing the primary user-plane function, so that the target eNB executes the primary user-plane function upon receiving the context information of the primary user-plane function from the source eNB, wherein the relocation REQ ACK message contains a user-plane address for the target eNB to receive data packets after relocation (S20); wherein the source eNB is a user-plane primary eNB, and the target eNB is a Secondary eNB, SeNB; the source eNB comprises the secondary user-plane function, and a secondary user-plane function of the source eNB keeps being executed in the relocation process, wherein for an uplink radio bearer, the primary user-plane function comprises: reordering data packets sent from the UE and processed by the secondary user-plane function; and for a downlink radio bearer, the primary user-plane function comprises: numbering data packets from an upper-layer network; and the secondary user-plane function comprises one or more of the following functions: a security function, a Radio Link Control, RLC, protocol stack function, a Media Access Control, MAC, protocol stack function and a Physical, PHY, protocol stack function. <EOS>