Abstract: Objective To discuss the application value of preoperative biopsy in the treatment of esophagus lesions by endoscopic submucosal dissection (ESD). Methods Clinical data of 177 patients (186 lesions) who had been diagnosed with esophagus intraepithelial neoplasia (EIN) or early cancer by preoperative biopsy from January 2008 to June 2013 in our digestive endoscopy center were summarized retrospectively, and the discrepancy of pathological diagnosis between endoscopic biopsies and specimens after ESD was analyzed. Results Among the 186 lesions of preoperative biopsies 23 cases were low-grade gastric intraepithelial neoplasia (LGIN), 143 cases were high-grade gastric intraepithelial neoplasia (HGIN) and 20 cases were early esophagus cancer. After ESD, 32 cases were low-grade gastric intraepithelial neoplasia (LGIN), 73 cases were high-grade gastric intraepithelial neoplasia (HGIN), 70 cases were early esophagus cancer and 11 cases inflammation. The total accordance rate of pathological diagnosis between preoperative biopsies and postoperative specimens was 95.2% (177/186) and the full consistency rate was 49.46% (92/186). Of LGIN, the full consistency rate was 56.5% (13/23), of HGIN was 44.76% (64/143) and of early cancer was 75.0% (15/20) which was the highest. Among the 23 cases in LGIN and 143 cases in HGIN of preoperative biopsies, respectively there were 3 cases (13.0%, 3/23) and 52 cases (36.36%, 52/143) whose pathological diagnosis were confrmed for cancer after ESD. There was statistical difference between the canceration rate of LGIN group and HGIN group (P< 0.05). Conclusion There is a certain gap between preoperative biopsy and postoperative pathology. More than one third of biopsy diagnosed HGIN are confrmed to be carcinoma after ESD, which need active measures so as not to bungle the illness.