To solve a problem of slow response speed of conventional thermal switches which use, as a thermal actuator material, paraffin whose volume changes with phase change, thereby taking time in volume change.

The thermal switch includes: a heat insulating support portion 3 supporting between the heat-source-side plate 1 and a heat-dissipating side plate 2; a contactor 4 separable from the heat-dissipating side plate 2; a flexible heat conduction section 6 connecting the contactor 4 and the heat-source-side plate; a contactor support section 5 swingably supporting the contactor; a movable member 7 movably supporting the contactor; a feed mechanism 8 moving the movable member forward or backward between a position where the contactor 4 is in contact with the heat-dissipating side plate 2 and a position where the contactor is out of contact with the heat-dissipating side plate 2; and a drive section 9 driving the feed mechanism 8.