Abstract: A thermocouple power generation unit, module, and device that generate electricity using a temperature difference, characterized by compact size and high efficiency. The thermocouple power generation unit comprises an insulating substrate, a cathode alloy section, a first insulating layer, an anode alloy section, a second insulating layer, a cathode conductive lead, and an anode conductive lead. The cathode and anode alloy portions respectively include multiple cathode and anode nanowires that are etched from cathode and anode alloy materials and arranged at equal intervals. A single pair of cathode and anode nanowires forms multiple power generation units, which are arranged in series, with their free ends respectively connected to the corresponding cathode and anode conductive leads. The connection points between the cathode and anode nanowires of the power generation units form multiple power generation points.