Abstract: An advanced voice/facsimile monitor system is developed. With a kind of advanced voice codec being used to perform speech compression/synthesis and the time division multiplexing technology being adopted in the design, and with the modern digital communication technology, the system can transmit 4 channels of high quality voice through one telephone line in real time, thereby realizing long distance and onenode to multinodes monitoring at the least channel cost; additionally the system can also telerecord FAX signal and the calling/called phone number. This system gains good response on probation and now is put into application.