A system for evaluating the performance of an electrical filter installed on an electrical power supply network passing through the screening of a Faraday enclosure, includes a transmit device for transmitting an inlet electrical pulse to the inlet of the filter. A receive and processing unit receives and processes the response electrical signal at the outlet of the filter corresponding to the pulse. A display displays the results obtained by processing the signal. The inlet electrical pulse is coupled to the power supply network and is conveyed thereby through the filter. The response is obtained from the outlet of the filter by decoupling.