Ultralow-temperature semiconductor refrigeration device

The utility model relates to an ultralow-temperature semiconductor refrigeration device, which solves the problem that the semiconductor refrigeration device can not reach a lower refrigeration temperature only by increasing the number of layers of semiconductor refrigeration sheets of a refrigeration stack. A bottom plate of a refrigeration pile radiator in the first air duct is connected with a hot end substrate of a semiconductor refrigeration sheet at the lowest part of a refrigeration pile in the refrigeration pile box through a first hole, and fins of the refrigeration pile radiator are positioned in the first air duct; the second air channel is connected and communicated with the first air channel, an inlet of the second air channel is provided with a first inlet fan, a cold-end radiator is arranged in the second air channel, fins of the cold-end radiator are correspondingly connected with fins of the refrigeration pile radiator to form a channel, and a bottom plate of the cold-end radiator is in heat