Device for testing function of telephone exchange

A device for testing a function of a telephone exchange during a production process includes a sending-end module for sending a test criterion, a receiving-end module for receiving a test criterion, an input/output interface module connected to a telephone exchange, a call connection indicating unit, a signal switching unit, and a controlling unit for controlling a test procedure. The device not only tests whether a call can be connected and whether a call can be answered, but analyzes local electrical characteristics of the telephone exchange at the telephone exchange-end. With the device, signals treated by an analog-to-digital conversion process can display various voice information of a voice signal conveyed by the telephone exchange, such that a damaged portion of the telephone exchange can be assessed whenever a test fails, thereby cutting test costs and production costs.