Abstract: ObjectiveTo observe mucosa lesions of different sections of esophagus among residents at high-risk of esophageal cancer for aetiologic research.MethodsIodine-staining esophageal endoscope examination was conducted and the esophageal tissues with negative iodine-staine were pathologically examined.ResultsAmong 9 526 participants,1 418 were pathologically examined.Biopsy samples were obtatined from upper section in 337 participants,upper-middle junction in 63,middle section in 560,middle-low junction in 64,and low section in 394,respectively.Overall 66,34 and 35 cases of esophageal cancer were found in upper,middle,and low sections,respectively.After adjustment of gender,age,education, average family income,the family history of esophaged cancer,smoking,and drinking were related to esophageal lesions of different sections,especially for middle esophagus section.ConclusionMiddle section is the predilection site of esophageal diseases and is prone to being affected by different risk factors.It is necessary to make a thorough study on risk factors of esophageal cancer in different sections.