A superconducting apparatus has a superconducting element (1), which is a member to be cooled and which exhibits a superconducting phenomenon; an electronic cooling element (2) composed of a cooling electrode (8) provided to the superconducting element (1) via an insulating layer (6), p-type and n-type semiconductor layers (2a, 2b) formed to be connected to the cooling electrode (8), heat-radiation electrodes (7) provided to the semiconductor layers (2a, 2b) independently of each other, and a heat-radiation plate (5) provided to the heat-radiation electrodes (7) via the insulating layer (6); lead wires (11, 9) for electrically connecting the superconducting element (1) and the electronic cooling element to external circuits, respectively. The superconducting element (1) and the electronic cooling element, which are integrally packaged, are installed within the first container (3). Internally sealed by an inert gas atmosphere, the first container (3) is installed within the second container (4). The second container (4) is internally sealed in a vacuum state.