A multilayer zinc oxide varistor without bismuth oxide system ingredients, and having variable breakdown voltages by controlling the thickness of the ceramic material; the varistor is bismuth-free and composed of zinc oxide as the primary constituent with alkaline earth element (Ba) as first additive, at least one of transition elements of Mn, Co, Cr, or Ni as second additives, at least one of rare earth elements of Pr, La, Ce, Nd or Tb as third additives and at least one of B, Si, Se, Al, Ti, W, Sn, Sb, Na, or K as rest additives, and the bismuth-free and zinc oxide based varistor exhibits an excellent ESD (Electro-Static Discharge) withstanding characteristic.