To enable a user to utilize communication use information stored in some communication terminal equipment even in optional communication terminal equipment of a mobile destination.

When a data up-load instruction is made in a state that call information to a specific user is stored in a terminal ancillary memory 21A of a communication terminal 20A where a user X registers a position the call information is up-loaded from the terminal ancillary memory 21A of the communication terminal 20A to a network ancillary memory 11 of a communication network 10 by a prescribed up-load sequence. Then after the user X moves to a communication terminal 20B and makes user position registration, when a data down-load instruction is made, the call information is down-loaded from the network ancillary memory 11 of the communication network 10 to a terminal ancillary memory 21B of the communication terminal 20B by a prescribed down-load sequence.