PURPOSE: To prevent the flowing of excess currents through a circuit by forming a metallic section fusion-cut by overcurrents or at a high temperature in series with a current path from an external electrode to an internal electrode and on the surface of a laminated structure.

CONSTITUTION: A positive temperature coefficient thermistor body 1 is formed by alternately laminating semiconductor ceramics 1aW1e composed of barium titanate, etc., and internal electrodes 2aW2d. In the internal electrodes 2aW2d, one ends of 2a and 2c are led out up to one end of the thermistor body 1, and one parts. 3, 4 are drawn out up to one side section of the thermistor body in the remainders 2a, 2d. The internal electrodes 2a, 2c are connected electrically to an external electrode 5a shaped at one end section of the thermistor body 1, and the remainders 2b, 2d are connected electrically to an external leading-out electrode 6 formed on the side circumferential section of the thermistor body 1. The external leading-out electrode 6 and an external electrode 5b shaped at the other end section of the thermistor body 1 are connected by a fuse 7 fusion-cut when overcurrents flow or the temperature of the body 1 is elevated. The fuse 7 is formed on the surface of the positive temperature coefficient thermistor body 1.