The invention relates to a soldering lug for segmented thermoelectric device connection and a preparation method thereof. The soldering lug has an A/B/A three-layer structure, A is a metal layer composed of low-melting-point components, and B is a mixed layer composed of low-melting-point components and high-melting-point components; the low-melting-point components are selected from at least oneof lead and an alloy thereof, tin and an alloy thereof, indium and an alloy thereof, zinc and an alloy thereof, and aluminum and an alloy thereof, and the high-melting-point components are selected from at least one of titanium, chromium, iron, cobalt, nickel, copper, germanium, zirconium, silver, gold, platinum, tellurium, antimony, niobium and cobalt. The A/B/A three-layer structure soldering lug is formed into a whole through pressure machining, can be freely cut, and can be conveniently used for connection of thermoelectric materials and connection between formed thermoelectric devices.