To provide a thin compact self-maintaining self-reset protective device which shuts off the current for a certain period from a generation of extraordinary heat.

This device comprises a substrate 2, a temperature keeping component 3 prepared on the substrate 2, a pair of lead terminals 4 which are prepared on the temperature keeping component 3 so that they face each other at a distance and connected to the temperature keeping component 3, a movable electrode 6 which has an on-off contact and is connected to the pair of lead terminals 4, and a cover which covers at least a part of the pair of lead terminals 4, the movable electrode 6 and the temperature keeping component 3.