Reversion of gastric precancerous lesion is important for the prevention of gastric cancer.There are different understanding and treatments about it,due to lacking of typical symptoms and physical signs.Deep understanding of its core pathogenesis is the key to exert superiority of traditional Chinese medicine and prevent gastric cancer.Evidences are collected from 4 aspects including macro phenomenon,microphenomenon,molecular mechanism and clinical pharmacology core pathogenesis and prescription of gastric precancerous lesion,initially establishing the principles and methods of the pathogenesis of the disease.