The present invention provides a protection device which provides a greater degree of freedom in a disposition of the bimetal switch as well as be able to more accurately control an actuation of the bimetal member of the bimetal switch. The protection device characterized in that the device comprises a bimetal switch wherein a first PTC member and a bimetal member are connected electrically in parallel with each other; and a second PTC member; and the bimetal member is disposed to be actuated by tripping of the second PTC member.