Objective To investigate and analyze the role of magnifying endoscopy in endoscopic submucosal dissection（ESD）in the treatment of early esophageal cancer and precancerous lesions．Methods Esophageal cancer patients in our hospital from January 2020 to July 2022 were selected as the observation objects,the investigator was a first-degree relative over 40 years old who found abnormal esophageal lesions through ordinary endoscopy,and underwent magnifying endoscopy,according to suspected esophageal mucosal epithelial nipple capillary loop（IPCL）changes,defined the nature of the lesion to estimate the invasion depth．Patients with suspected early esophageal cancer and precancerous lesions were given ESD treatment,and those with suspected progressive esophageal cancer underwent surgical treatment,and were sent to the whole specimen for pathological examination．Results A total of 128 patients with first-degree relatives of esophageal cancer over 40 years old were found to have simultaneous enlarged endoscopy simultaneously through common endoscopy,among which 102 patients had obtained overall pathological specimens by ESD and surgery．Comparing the preoperative diagnosis of magnifying gastroscopy and the postoperative overall pathological specimens,the overall accuracy of magnifying endoscopy for the diagnosis of early esophageal lesions was 87.3%,the sensitivity of detecting early esophageal squamous cell carcinoma was 97.8%,specificity was 15.4%,the positive predictive value was 88.8%,and the negative predictive value was 50%．In terms of invasion level,the overall accuracy of magnifying endoscopy for the depth diagnosis of early esophageal squamous cell carcinoma was 69%,90.6% accuracy and 70.6% sensitivity of B1 vessels,32.2% and 76.9% of B2 vessels,66.7% and 33.3% of B3 vessels．Conclusions The magnifying endoscopic treatment of patients with early esophageal cancer and precancerous lesions under ESD can accurately diagnosis the nature of esophageal lesions,improve the detection rate of lesions,and has high practical value．