A plug connector includes: a ground contact conductor; an insulating housing; and a signal contact conductor. The ground contact conductor includes: a cylindrical main body having a slit that extends in an extending direction thereof; a pair of arms protruding from respective edges forming the slit of the main body in a radially outward direction of the main body; and fixing portions configured to fasten around the pair of arms from the exterior. Each fixing portion is provided with a protrusion protruding toward the corresponding arm and positioned at the center of the fixing portion in a protruding direction of the arms. In a state in which the arms are fastened with the fixing portions, the protrusions are in contact with the arms, and the arms and the fixing portions are separated from each other by the presence of the protrusions.