Abstract: The serum Lipid peroxides(Lpo) levels among normal population, patients with mild and severe hyperplasia for esophageal epithelium and patients with esophageal cancer (ECa) were determined by the thiobarbiturie acid method. The results showed that the serum Lpo levels increased gradually with the development of carcinogenesis. The serum Lpo values were significantly higher in patients with ECa than those of normal population and patients with hyper plasia for esophageal epithelium. These suggested that there be a close correlation between lipid peroxidesion and esophageal cancer. The results also suggested that there exist a problem of concentration for Lipid peroxides to induce carcinogenesis.