An electrical coaxial connector comprising a body made of insulator to be put on a circuit board, a signal-joining contacting conductor held by the body, and a grounding contacting conductor formed into a cylindrical shape and held also by the body for surrounding the signal-joining contacting conductor on the circuit board, wherein the grounding contacting conductor has an arm portion extending toward the circuit board from one of ring-shaped ends of the grounding contacting conductor, which is more distant from the circuit board than the other, a grounding terminal portion is formed at an end of the arm portion to be soldered to a ground-potential terminal provided on the circuit board, and each of the grounding contacting conductor and the arm portion is resilient.