Abstract: A thermal switch comprising a plurality of outer terminals respectively having a fixed contact, a movable contact spring divided into a plurality of mutually parallel contact spring parts each having a movable contact for contacting with and separating from the fixed contact and a plurality of bimetals respectively operating at differently set temperatures and provided so as to independently actuate the respective contact spring parts, whereby resetting-type contacts are reliably opened and closed in response to fluctuations in the atmospheric temperature through one of the bimetals which has a relatively lower first set-temperature and, when the particular bimetal of the relatively lower first set-temperature fails to operate and the atmospheric temperature further rises, non-resetting-type contacts are reliably opened through the other bimetal having a relatively higher second set-temperature.