Methods and apparatuses consistent with the present invention relate to a cellular phone having a mailing function and a mail security processing method for the same. The user inputs a secret number and then selects a mail folder to display a security setting/releasing mail folder list. When the user selects a mail folder, the security processing is executed for the mail folder. The folder is not shown in an ordinary mail folder list. To release the setting of security implemented by the security processing, the user displays the security setting/releasing screen, inputs a secret number, and selects a mail folder. In a security setting/releasing mail folder list, the mail folder for which the security processing has been executed is displayed. The user selects the folder, and as a result, the setting of security is released.