A temperature element may be provided with: a combination of a p type semiconductor and an n type semiconductor disposed separated from each other; a metal well, which has a mounting part on which a container for DNA samples is directly mounted and which is connected to both the p type semiconductor and the n type semiconductor individually; an electrode and heat dissipating plate that is connected to the p type semiconductor and to which a voltage is applied by a temperature control section; and an electrode and heat dissipating plate that is connected to the n type semiconductor and to which a voltage is applied by the temperature control section. The shape of the metal well is formed into substantially the same shape as the outside shape of the container for DNA samples.