The receptacle connector includes a central terminal mechanically and electrically connecting with a core wire of a coaxial cable connected to a plug connector, and an outer terminal mechanically and electrically connecting with an external conductor surrounding the core wire with an internal electrical-insulator being sandwiched therebetween, the central terminal including a first contact making contact with the core wire, and a second contact electrically connected to the first contact, passing through under the outer terminal and extending to the outside of the outer terminal, the second contact being formed with at least one of a cut-out and an opening in an area where the second contact overlaps the outer terminal.