There is provided a communication apparatus that can reduce the labor and time required to notify others of a change in a user's e-mail address and can lessen the burden on a recipient of e-mail of rewriting a telephone directory list. On a sender terminal side, only information on e-mail addresses is extracted from a telephone directory list and is copied to a temporary storage buffer. E-mail is automatically generated based on a format conforming to notification contents selected by the user and is transmitted to the e-mail addresses that have been copied into the temporary storage buffer. On a recipient terminal side, a title of the received e-mail is analyzed and when the e-mail is determined to relate to a telephone number notification, a character string required for the telephone number is obtained from the e-mail contents and this telephone number information is reflected in the telephone directory list.