Mobile communication system, mobile terminal, subscriber information management apparatus, mobile network system, location area information registration method and call control method

A mobile terminal can be loaded with a plurality of subscriber identity module cards at the same time, and register the condition to a mobile communication network. The mobile terminal comprises detects a loading of a recording medium (such as an IC card like the SIM card), and transmits, when the detecting means detects at least two recording media, first subscriber identity information (e.g. IMSI, TMSI, etc.) corresponding to a first recording medium and second subscriber identity information corresponding to a newly detected recording medium, to the subscriber information management apparatus such as a visitor location register (VLR). The subscriber information management apparatus registers location area information of the first subscriber identity information as location area information associated with the second subscriber identity information.