A thermoelement and a thermovalve incorporating the same, in which reliable operation is achieved with a simple internal structure, and there is no risk of contaminant jamming. The thermoelement includes a casing, a mounting portion, a shaft, a heat-sensitive medium, and a seal member for drawing the shaft into the casing when the heat-sensitive medium expands. The thermovalve includes a body including a valve body linked to a shaft of a thermoelement, and a seating part on/from which the valve body can be seated/separated.