Abstract: Metallothionein( MT) is a metal- binding,cysteine- rich protein,low molecular weight,which is widely distributed throughout the body.Numerous studies confirms that MT has significant effects on participation in heavy metal detoxification,regulating the body 's metabolism of trace elements,gene expression and preventing oxidative.MT has a prominent role in vivo antioxidant with in- depth studying.The structure,classification,antioxidant mechanism of MT and its application in terms of antioxidant products were reviewed in this paper. To provide a theoretical reference for MT in vivo antioxidant and the development of related research antioxidant products.