ISDN terminal apparatus

An object of the invention is to provide an ISDN terminal apparatus in which a facsimile and an ISDN interface are integrated and the functions thereof are merged to avoid waste. An ISDN line control unit (22) is disposed between an ISDN line (21) and a facsimile unit (23). When detecting an occurrence an abnormal condition in the ISDN line (21), a control CPU (29) of the ISDN line control unit (22) directly transmits the occurrence of the abnormal condition to a CPU of a control unit (31) of the facsimile unit (23). When detecting an occurrence of an abnormal condition in the facsimile unit (23) the CPU of the control unit (31) of the facsimile unit (23) directly transmits the occurrence of the abnormal condition to the CPU (29) of the ISDN line control unit (22). A control panel (42) and a display (41) can be used for both performing settings of the ISDN line control unit (22) and operating the facsimile unit (23). Since an automatic answering and recording unit (25) is controlled by the ISDN line control unit (22), a facsimile communication and telephone automatic answering and recording can simultaneously be performed by using the two lines of the ISDN line.