PURPOSE: To enhance the service performance for an automatic dialing function based on communication information by making automatic dialing to a line based on a number included in user information designated by a multi-functional telephone set in an output list.

CONSTITUTION: A caller ID and user information stored in a memory 7 by the incoming, call operation are confirmed as a list output by a network information read service. In this case, a central control unit 6 reads the caller ID and the user information from the memory 7 and displays them on the display device of an extension telephone set 1a. When the user of the telephone set la makes a request dialing to a desired ID in a caller list based on the display, the user selects a relevant ID among the displayed ID numbers. When the selected ID corresponds to the caller ID, the relevant caller ID is read from an area corresponding to the memory 7 and the number is automatically dialed to the caller ID.