A connector assembly includes an electrical connector, a metal shielding cage and a fastener. The electrical connector includes an insulating body and a number of conductive terminals. The insulating body includes a mounting surface configured to be mounted on a circuit board and a mating slot configured to receive a mating connector. The metal shielding cage is shielded on a periphery of the electrical connector. The metal shielding cage includes a receiving chamber in communication with the mating slot for receiving the mating connector. The fastener passes through the circuit board and is fastened to the electrical connector.