A communication control system capable of reducing the traffic amount, CPU's processing load and channel bands related to a location registering process. In this system, a transmitting/receiving part (301) of a base station apparatus (300) receives a call request message transmitted from an access gateway apparatus (200) and addressed to a wireless terminal apparatus, and a location registration determining part (306) determines whether a wireless link to the wireless terminal apparatus to be called can be established. If the wireless link has been established, a position registering part (307) registers an IP address established at the transmitting source of the call request message, and the transmitting/receiving part (301) transmits, to the access gateway apparatus (200), a call response message indicative of accommodating the wireless terminal apparatus in response to the call request message.