A stress relief device is provided for a connector. The connector is connected to a cable and configured for cooperating with a complementary connector along a longitudinal axis. The stress relief device includes: an anchor configured for being placed around a portion of the cable so as to allow a stress relief of the portion of the cable, the portion of the cable being adjacent to the connector; a shell configured for being connected to the anchor and for at least partially wrapping the connector; and a locking system configured for connecting and locking the shell to a similar shell of a similar stress relief device for the complementary connector. The stress relief device is detachably mountable on the connector and is configured such that its mounting/dismounting does not require any change in the connection/disconnection of the connectors to one another.