A receptacle connector used as an electrical connector. The receptacle connector includes: a housing in which a receiving space is formed, a connection target being inserted in the receiving space; a plurality of contacts being arranged parallel to one another, having a plurality of signal line contacts and a plurality of ground contacts, and being placed with every two adjacent signal line contacts for transmitting signals interposed between two ground contacts; a supporting member made of an electrically-insulating synthetic resin material, and configured to integrally support and fix thereto the plurality of contacts; and a common contact made of a conductive resin material and configured to be provided with a certain gap from each of the plurality of ground contacts to electrically connect the plurality of ground contacts. The plurality of contacts integrated together by the supporting member are received in the receiving space.