Communication system, mobile communication apparatus and switching method of subscriber identification information

A communication system, a mobile communication apparatus and a switching method of subscriber identification information are disclosed. The switching method includes following steps. First subscriber identification information of a first subscriber identification card is stored into a home location register (HLR) of a mobile telecom network by a first mobile communication device. A request instruction is sent by a second mobile communication device. The request instruction is verified by the mobile telecom network. If the request instruction passes the verification, the first subscriber identification information is duplicated and transmitted to the second mobile communication device. When users do not have their original subscriber identification card, the users can send specific request instructions via new mobile communication devices, such as to request for accessing the original subscriber identification information. If the request instructions pass the verification, the mobile telecom network transmits the original subscriber identification information stored in the home location register to the new mobile communication devices.