To provide a mobile telephone capable of notifying arbitrary telephone book data also during a call by referring to the data.

When the mobile telephone 1 is in a call state, a telephone book function block 12 is started, thus resulting in an off-hook state when one's call party requests the notification of a telephone number. The mobile telephone 1 retrieves a telephone number corresponding to the key operation of a key input block 19 from the telephone function block 12, displays the retrieved data onto a display block 20, and stores them at a retrieved result storage block 13 as character strings. The mobile telephone 1 converts the telephone number stored at the retrieved result storage block 13 as character strings in a speech synthesis processing block 14 as sound data; and an on-hook state, where the call can be made, results before the notifying one's call party via a voice input processing block 15 and a portable telephone basic mechanism control block 11 for returning to the call state again.