PURPOSE: To eliminate assuredly a misanswer, by displaying a mail arrived at the own terminal along with a list of mails to which the answers are required at each terminal.

CONSTITUTION: When a mail is transmitted to a terminal B from a terminal A, a document mail is first produced by making use of a word processing function of the terminal A to store the mail temporarily in a local character file 43. At the same time, the sending address information of a mail including the presence or absence of a request for answer is fed through a keyboard 41. If a request is given for the transmission of the mail under such conditions, the contents of the file 43 is transferred to a document file 2 by a CPU3 and the designating input of the sending address is stored in a mail table 31 of the CPU3. The CPU3 displays a message on a display 42 of the terminal B of the receiving side when a new mail arrives at the table 31 and then displays the contents of the file 2 or the mail list addressed to the terminal B on the display 42 in accordance with the request of the terminal B.