The invention presents a PTC thermistor which is high in adhesive strengths of inner- and outer-layer electrodes composed of metallic foil respectively stuck to conductive sheets, and has a larger current breaking characteristic. It contains a laminated body (13) which is formed by alternately laminating a plurality of conductive sheets (14) and an inner-layer electrode (11) composed of metallic foil having first plated layers (12) so that the conductive sheets (14) can become the outermost layers, an outer-layer electrode (18) positioned at the outermost layer of the laminated body (13), and having a second plated layer (16) on a side facing the inner-layer electrode (11), and side-face electrode layers 20) disposed at facing sides of the laminated body 913) for connecting electrically the inner-layer electrode (11) and outer-layer electrode (18).