A superconducting device according to an example embodiment includes: a superconducting chip; an interposer on which the superconducting chip is mounted; a socket that is arranged to face the interposer and includes a movable pin and a housing supporting the movable pin; and a board that is arranged to face the socket and includes a connector serving as an input/output with respect to the outside. In the board, one end of a terminal of a via hole is electrically connected to one end of a terminal of the movable pin, and a hole diameter of the via hole is smaller than a diameter of a tip portion of the movable pin connected to the via hole.