An electrical connector includes a nonconductive casing defining a cavity therein having an opening on a front face of the casing for receiving a mating connector. A terminal support post is arranged in the cavity. The post has a plurality of channels defined therein for receiving conductive members that are engageable with counterpart conductive terminals of the mating connector. A shielding member is fit over and surrounds the casing. The shielding member has conductive legs extending therefrom for grounding purposes. Two spring plates extend from the shielding member into the cavity for physically engaging with a conductive shell of the mating connector to mechanically retain the mating connector in the cavity and electrically ground the shell of the mating connector. The electrical connector further includes two additional retaining plates. Each retaining plate has a base section interposed between the casing and the shielding member and electrically connected with the shielding member. The retaining plate has an engaging section resiliently supported on the base section by an arcuate section which biases the engaging section against the conductive shell of the mating connector for securely retaining the mating connector in the cavity and electrically grounding the shell of the mating connector.