The present invention relates to an electrical connector, comprises a housing; a base body having a tongue piece, one surface of the tongue piece is provided with a plurality of first terminal slots, the other surface of the tongue piece is provided with a plurality of second terminal slots, and a gap is provided in the middle portion of the tongue piece; a first terminal assembly respectively received in the first terminal slots; a second terminal assembly respectively received in the second terminal slots; and a grounding piece inserted in the gap of the tongue piece, a contact portion is provided by extending from the end of the grounding piece, when assembly the contact portion is in contact with a grounding terminal of any said terminal assemblies mentioned above, so effects of grounding and prevention of static electricity can be achieved.