A thermoelectric apparatus includes a first and a second assemblies, at least a first and a second heat conductors. The first assembly includes a first and a second substrates, and several first thermoelectric material sets disposed between the first and second substrates. The first substrate has at least a first through hole. The second assembly includes a third and a fourth substrates, and several second thermoelectric material sets disposed between the third and fourth substrates. The fourth substrate has at least a second through hole. Each of the first and second thermoelectric material sets has a p-type and an n-type thermoelectric element. The first and second heat conductors respectively penetrate the first and second through holes. Two ends of the first heat conductor respectively connect the second and fourth substrates, while two ends of the second heat conductor respectively connect the first and third substrates.