A quantum device includes a quantum chip including a superconducting quantum circuit; an interposer including mounting the quantum chip on a first surface thereof; a housing having openings penetrating from a first surface of the housing opposing a second surface of the interposer to a second surface of the housing with probe pins housed in the opening, a board with a first surface facing the second surface of the housing; and one or more spacers between the first surface of the housing and the second surface of the interposer to ensure a clearance between the first surface of the housing and the second surface of the interposer facing the first surface of the housing.