The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. According to an aspect of the embodiments of the present disclosure, a method for supporting handover is provided, comprising: receiving a message from a central unit control plane entity of a target base station; receiving a data packet from a source base station; and discarding a packet data convergence protocol (PDCP) service data unit (SDU) including the PDCP sequence number (SN) in the received data packet according to the indication of the message.