A cell handover method, the method comprises: receiving, by a source wireless gateway, a measurement report from a terminal, wherein the source wireless gateway is a gateway corresponding to a source cell; determining, by the source wireless gateway, a target wireless gateway based on the measurement report, wherein the target wireless gateway is a gateway corresponding to a target cell, and wherein each of the source wireless gateway and the target wireless gateway has a function of authentication for access of the terminal, a handover of the terminal, mobility management and user context and bearer management of the terminal in an idle state, storing subscription information of a user, completing routing and forwarding of packet data, providing at least one of lawful interception-related functions, assignment of a user address, execution of policy control and a charging rule, and lawful interception; sending, by the source wireless gateway, a handover request message to the target wireless gateway; sending by the source wireless gateway, a handover instruction message to the terminal when receiving a handover request acknowledgment message from the target wireless gateway; receiving, by the source wireless gateway, a release resource message from the target wireless gateway, wherein the release resource message is sent after the target wireless gateway sends an update request to a target port of a forwarding device, and the update request is used to instruct the forwarding device to update a port identifier corresponding to a target address to a target port identifier of the target port; and releasing, by the source wireless gateway, a radio bearer between the terminal and the source wireless gateway based on the release resource message; wherein the forwarding device is a switch, the update request is a gratuitous address resolution protocol, ARP, packet, and both the source wireless gateway and the target wireless gateway have functions of a two-port layer 2 network device, where the two-port layer 2 network device includes a layer 2 tunnel and a bridge; or the forwarding device is a router, the update request is a link state, LS, update packet, and both the source wireless gateway and the target wireless gateway pre-establish an open shortest path first neighbor relationship with the router. receiving, by a source wireless gateway, a measurement report from a terminal, wherein the source wireless gateway is a gateway corresponding to a source cell; determining, by the source wireless gateway, a target wireless gateway based on the measurement report, wherein the target wireless gateway is a gateway corresponding to a target cell, and wherein each of the source wireless gateway and the target wireless gateway has a function of authentication for access of the terminal, a handover of the terminal, mobility management and user context and bearer management of the terminal in an idle state, storing subscription information of a user, completing routing and forwarding of packet data, providing at least one of lawful interception-related functions, assignment of a user address, execution of policy control and a charging rule, and lawful interception; sending, by the source wireless gateway, a handover request message to the target wireless gateway; sending by the source wireless gateway, a handover instruction message to the terminal when receiving a handover request acknowledgment message from the target wireless gateway; receiving, by the source wireless gateway, a release resource message from the target wireless gateway, wherein the release resource message is sent after the target wireless gateway sends an update request to a target port of a forwarding device, and the update request is used to instruct the forwarding device to update a port identifier corresponding to a target address to a target port identifier of the target port; and releasing, by the source wireless gateway, a radio bearer between the terminal and the source wireless gateway based on the release resource message; wherein the forwarding device is a switch, the update request is a gratuitous address resolution protocol, ARP, packet, and both the source wireless gateway and the target wireless gateway have functions of a two-port layer 2 network device, where the two-port layer 2 network device includes a layer 2 tunnel and a bridge; or the forwarding device is a router, the update request is a link state, LS, update packet, and both the source wireless gateway and the target wireless gateway pre-establish an open shortest path first neighbor relationship with the router.