PURPOSE: To obtain a nonlinear resistor producible by a simple method at low cost without complicated composition and grain boundary layers, having excellent nonlinearity and high varistor voltage, and having excellent durability against repeated load of overvoltage exceeding the varistor voltage.

CONSTITUTION: The nonlinear resistor is composed of Cu and/or Ni oxide particles of a sintered compact having CuO and/or NiO as main components, and the oxygen concentration of each particle constituting the sintered compact becomes lower the more it approaches the particle center. This nonlinear resistor is manufactured by press-molding high-purity Cu and/or Ni powder, and sintering the compact finely in an oxygen atmosphere after that.