A mobile communication terminal adapted to selectively use a plurality of caller own numbers, comprising: a number information memory means adapted to store a plurality of other-party numbers and to store for each of said plurality of other-party numbers, a corresponding caller own number; a caller own number storing means adapted to store a plurality of caller own numbers which can currently be used; a call origination designating means adapted to designate by a user an originating call to a user designated other-party number; a judgment means adapted to judge whether or not the designated other-party number to which an originating call has been designated by the call origination designating means is present in the number information memory means; a retrieval means adapted to retreive from the caller own number storing means a caller own number corresponding to the designated other-party number when the designated other-party number has been judged as being present by the judgment means; a first call origination means adapted to call the designated other-party number using the retrieved caller own number retrieved by the retrieval means to originate the call; characterized by a selection means adapted to select, by a user, any one of the plurality of caller own numbers stored in the caller own number storing means when the judgment means judges that the designated other-party number is not present or when the caller own number corresponding to the designated other party number is not stored in the number information memory means; a second call origination means adapted to call the designated other-party number using the selected caller own number selected by the selection means, when the judgment means judges that the designated other-party number is not present or when the caller own number corresponding to the designated other party number is not stored in the number information memory means; an a number information registration means adapted to register in the number information memory means, either one of (i) the designated other-party number and the used caller own number by the second call origination means, being corresponded with each other when the judgment means judges that the designated other-party number is not present, or (ii) the caller own number used by the second call origination means, being corresponded with the designated other-party number when the caller own number corresponding to the designated other party number is not stored in the number information memory means. a number information memory means adapted to store a plurality of other-party numbers and to store for each of said plurality of other-party numbers, a corresponding caller own number; a caller own number storing means adapted to store a plurality of caller own numbers which can currently be used; a call origination designating means adapted to designate by a user an originating call to a user designated other-party number; a judgment means adapted to judge whether or not the designated other-party number to which an originating call has been designated by the call origination designating means is present in the number information memory means; a retrieval means adapted to retreive from the caller own number storing means a caller own number corresponding to the designated other-party number when the designated other-party number has been judged as being present by the judgment means; a first call origination means adapted to call the designated other-party number using the retrieved caller own number retrieved by the retrieval means to originate the call; characterized by a selection means adapted to select, by a user, any one of the plurality of caller own numbers stored in the caller own number storing means when the judgment means judges that the designated other-party number is not present or when the caller own number corresponding to the designated other party number is not stored in the number information memory means; a second call origination means adapted to call the designated other-party number using the selected caller own number selected by the selection means, when the judgment means judges that the designated other-party number is not present or when the caller own number corresponding to the designated other party number is not stored in the number information memory means; an a number information registration means adapted to register in the number information memory means, either one of (i) the designated other-party number and the used caller own number by the second call origination means, being corresponded with each other when the judgment means judges that the designated other-party number is not present, or (ii) the caller own number used by the second call origination means, being corresponded with the designated other-party number when the caller own number corresponding to the designated other party number is not stored in the number information memory means. (i) the designated other-party number and the used caller own number by the second call origination means, being corresponded with each other when the judgment means judges that the designated other-party number is not present, or (ii) the caller own number used by the second call origination means, being corresponded with the designated other-party number when the caller own number corresponding to the designated other party number is not stored in the number information memory means.