Abstract: By a search frequency information acquisition processing unit (11), search frequency setting information of a radio base station is received from a PC (30), and a condition such as a country name or the like is stored in a user setting information storage memory (21) whereas the frequency information to be used in that country is stored in a frequency information table (22). On the basis of the information of the search frequency stored in the user setting information storage memory (21) and the frequency information table (22), a surrounding radio base station is searched by a radio base station search processing unit (14).

Abstract: In a mobile communication terminal device 1: a storage means 23 has first through fifth registration regions; a business with which communication can be established extraction means 21a analyzes information carried by a radio wave which is received at the current position and extracts communication businesses with which communication can be established; and a communication business selection means 21b selects a communication business to be employed based upon the results of extraction by the business with which communication can be established extraction means 21a and upon the contents registered in the first through the fifth registration regions. As a result, during roaming, this mobile communication terminal device is enabled to select, among a plurality of communication businesses with which communication can be established, a communication business for which the cost of connection is cheap.