An electrical connector includes an insulation body, a seat, and a positioning plug. The seat is disposed on an outer peripheral surface of the insulation body. The seat includes a tunnel defined through the seat to form an inlet and an outlet. The outlet and a front surface of the insulation body face the same side. The seat further includes a slit and one or more first bumps disposed on an inner wall of the slit. The positioning plug includes a sliding block and rib. The sliding block movably disposed in the tunnel via the inlet with the rib movably disposed in the slit. The positioning plug further includes a second bump disposed on a lateral side of the rib facing the first bump. When the sliding block moves to an installation position, the first bump stops the second bump to fix the sliding block at the installation position.