Embodiments of the present invention provide a service forwarding method and device. The method includes receiving an uplink packet of a base station that is sent by a user-end provider edge (UPE) device over a transport tunnel. The uplink packet carries an Internet Protocol (IP) address of the base station and an identifier of the transport tunnel. The method further includes establishing a mapping relationship between the IP address of the base station and the identifier of the transport tunnel according to the uplink packet, and sending a downlink service packet to the UPE device over the transport tunnel according to the mapping relationship. A destination IP address of the downlink service packet is the IP address of the base station.