In multiple communication networks operated by different carriers, when a roaming mobile station performs communication with a roaming communication network PLMN, the communication network was able to recognize only the radio capability reported by the mobile station. When the communication network and mobile station differ in radio capability they support, problems arise in that the roaming mobile station sometimes cannot establish a user data channel and its success rate can reduce, and sometimes can operate in an unintended manner. The mobile station has a PLMN decision internal list (30) and radio capability internal list (31). A to-be-connected network decision section (12) outputs detailed information on a to-be-connected communication network PLMN, and decides the to-be-connected communication network PLMN. A radio capability selecting section (13) selects radio capability values from the radio capability internal list (31), and reports the radio capability report list to the communication network to be connected.