Method for managing multicast group in mobile communication system

A multicast service of a 3GPP Universal Mobile Telecommunications System (UMTS) is disclosed. By allowing an RNC to manage multicast group member information by multicast services on multicast areas, when a user terminal being currently provided with an MBMS service moves, the RNC sends information on the movement of the terminal to a core network. Since the RNC notifies the core network of the terminal's movement selectively on the basis of the multicast group member information by multicast services on the multicast area, the network resource can be effectively used, and especially, unnecessary transmission of terminal's movement information from the RNC to the multicast group managing entity of the core network can be prevented.