A communication terminal device and a method for controlling the same which can operate a mail restriction function effectively without increasing a mail address registered for the mail restriction function are provided. The transmission and the reception of the mail is restricted by storing by a domain conversion table a corresponding relationship between an original domain by the automatic address conversion unit and the domain after the conversion, acquiring by the original domain acquiring unit the original domain based on the domain of the mail address converted by the automatic address conversion unit by referring to the domain conversion table, and controlling by the mail transmission and reception control means the transmission and the reception of the mail by comparing the mail address replaced with the domain of the mail address of the transmitting/receiving mail by the original domain acquired by the original domain acquiring unit with the registered mail address.