A telephone terminal capable of keeping a line to the other party's telephone terminal connected through a telephone line network in a connected state even after an output destination and an input source of audio signals are switched to an audio input/output unit. In a multifunction machine serving as the telephone terminal, a transmission path to be used for input/output of audio signals from/to an outside source is switched to an audio cable when a switch key is pressed during a voice call through the telephone line network. If an Internet call function is used at a PC, a voice call by the Internet call function may be performed indirectly by using a transmitter/receiver. The multifunction machine may automatically disconnect the line through the telephone line network when receiving a BT from the telephone line network after the transmission path is switched to the audio cable.