An object of the present invention is suppressing a mail transmission loop between the communication terminals. A communication terminal 1 according to the present invention includes: a communication unit 10 for receiving a mail from a transmitter; a flag confirming unit 18 for confirming whether an automatic reply flag is attached or not to the received mail; an automatic reply time confirming unit 19 for confirming the number of times of automatic replies; an automatic reply determining unit 20 for determining whether to perform the automatic reply function or not based on presence or absence of the automatic reply flag and the number of times of automatic replies; and a mail transmitting unit 23 for transmitting the automatic reply mail to the transmitter when the automatic reply function is determined to be performed; wherein the number of times of automatic replies is changed every time the automatic reply function is performed, and when the automatic reply flag is attached to the received mail and the number of times of automatic replies reaches a given value with respect to the received mail, the automatic reply determining unit 20 determines not to perform the automatic reply function.