The kit is for quantitative detection and the procedure of this assay is simple, easy and hardly influenced by physiological active substances and body fluid. The epitope of this antibody we used in this kit located at NH2 terminals and acetylated peptides in MT. MT I and II which have commonly NH2 terminals sequence can reacted against this antibody. Metallothionein (MT) which is Cd binding protein have discovered from horse kidney by Margoshe and Vallee in 1957. MT is present in all animal cells and has strong affinity against another heavy metal. The physiological role are concerned in detoxication of organic metal, metabolic regulation of bioessential metal, protection from stress and free radical . However, to obtain high affinity anti MT antibody was very hard because MT is cysteine rich (about 30%), low molecular weight protein and by the absence of aromatic amino acid in this structure. Therefore, the high sensitive ELISA system has not established and difficult to investigate the behavior of MT in vivo. We developed anti MT antibody and established the high sensitivive ELISA system for determining human and animal MT. The epitope of this antibody is located at NH2 terminals acetylated peptides in MT, therefore can assay native MT. In addition, NH2 terminals of MT is high conserved sequence in many animal species, therefore almost animals MT can measure in this ELISA kit.