A method for forwarding downlink packets based on S1 handover is disclosed. The method includes: numbering a packet not processed by using PDCP according to a message that comprises PDCP Serial Number (SN) information if downlink packets to be forwarded include the packet not processed by using PDCP; and sending the downlink packets to the UE according to the PDCP SN corresponding to the packet included in the downlink packets. A method for forwarding uplink packets based on S1 handover is disclosed. The method includes: receiving state report information of the packet sent by the target eNodeB; and sending the packet according to the state report information of the packet. Another method for forwarding downlink packets based on S1 handover and an eNodeB are disclosed. Through the embodiments of the present disclosure, the packets are forwarded without loss in the case of S1 handover.