PURPOSE: To improve the discharge withstand current rating characteristics of the title resistor by providing an overcoat layer formed by baking polytitanocarbosilane to the side faces of a sintered body composed principally of zinc oxide and provided with side-face high-resistance layers of Zn2SiO4 and/or Zn7Sb2O12.

CONSTITUTION: A sintered body 1 provided with side-face high-resistance layers 2 of Zn2SiO4 and/or Zn7Sb2O12 is heat-treated by baking polytitanocarbosilane within s temperature range of 450-700°C after overcoat layers 3 are formed on the side faces. After the heat-treatment, polytitanocarbosilane is applied to the side faces of the sintered body 1 and baking treatment is performed on the sintered body 1 within a temperature range of 250°C 700°C. Then both end faces of the sintered body 1 thus produced are polished to flat surfaces and spraying electrodes 4 of aluminum are formed on the end faces. Therefore, the adhesive strength between the polytitanocarobosilane and sintered body 1 can be improved sufficiently and the discharge withstand current rating characteristics can be improved.