Disclosed is a cable adaptor comprising a first member which is conductive and comes into contact with a signal pin of the cable, a second member disposed outside the first member and coupled to the first member, a third member which is conductive and disposed outside the second member, and a contact pin fixed to the first member. Here, the first member includes a first body coupled to the second member and a first contact portion which extends from the first body and comes into contact with the signal pin. The third member includes a second body coupled to the second member and a second contact portion which extends from the second body and comes into contact with the outer conductor. A plurality of first contact points of the signal pin and the first contact portion are arranged at same intervals along a circumferential direction of the signal pin.