A system and method of charging for user traffic without including signaling costs in a wireless communication system is provided. In a system and method of charging a user equipment (UE) in a gateway node in a mobile communication system having a serving support node within a radio network connected to the UE and the gateway node for connecting the radio network to a home server in an external network, the gateway node acquires from the external network the address of a home server that provides a service requested by the UE, stores the home server address, clears charging information collected with respect to signaling generated prior to the allocation of the home server address, and re-collects charging information about the service that the UE receives.