Provided are a method for distinguishing different service flows when an M2M terminal transmits/receives data by using an M2M group ID (MGID) in a broadband wireless communication system supporting M2M communication, especially when each of the difference service flows are allocated with MGIDs from different network entities, and a terminal for providing same. According to one embodiment of the present invention, a method for the terminal receiving a multicast service for group terminals from a base station, in a wireless access system, comprises the steps of: receiving from the base station a broadcasting message including at least one identifier, wherein the at least first identifier identifies a group zone that is allocated to the base station; sequentially allocating an index to the at least one first identifier; and receiving from the base station a second identifier for identifying the multicast service and multicast data based on the index.