An object is to provide a communication terminal capable of using a newly-generated network slice or service. A communication terminal (10) according to the present disclosure includes a communication unit (11) configured to receive a parameter related to SM-NSSAI (Session Management-Network Slice Selection Assistance Information) from a core network when subscriber information of the communication terminal itself managed in the core network or a location of the communication terminal itself is changed, and a control unit (12) configured to update NSSAI by using the parameter related to the SM-NSSAI, the NSSAI being managed to select a network slice.