An automatic facsimile signal analyzing system includes a switch unit, a service trunk, a signal identification trunk, a facsimile communication determination unit, and a control unit. The signal identification trunk restores a facsimile control signal from a modulated and encoded facsimile signal on the set speech path and performs collection of communication state information and detection of a start of facsimile communication on the basis of the restored facsimile control signal. The facsimile communication determination unit permits an operation of the signal identification trunk when the classification result from the service trunk represents a type other than the voice signal and analyzes the communication state information from the signal identification trunk. The control unit performs switching/connection control of the switch unit, connects the service trunk and the signal identification trunk, both of which are in an idle state, to the set speech path upon setting of the speech path, disconnects the service trunk from the speech path when the classification result is output, and disconnects the signal identification trunk from the set speech path when the classification result from the service trunk represents the voice signal and when a call corresponding to the set speech path is ended.