Abstract: Objective To evaluate the efficacy of oral corticosteroids in preventing esophageal stenosis after large area esophageal endoscopic submucosal tunnel dissection (ESTD). Methods The patients undertook esophageal ESTD were included from January 2014 to January 2018. The inclusion criteria was single lesion of esophageal early esophagus cancer with the extent more than 3/4 of circumferential degree. According to the inclusion time, the patients were divided into the trial group (ESTD + oral corticosteroids) and the control group (simple ESTD). The incidence of the total esophageal stenosis, intractable esophageal stenosis, the remission rate of dysphagia and the period from the dysphagia present were observed and compared in the two groups. Results A total of 101 cases of esophageal ESTD patients were included. There were 48 cases in the trial group, 28 cases of male and 20 cases of female, with an average age of (62.98±7.52) years; 53 cases in the control group, 28 cases of male and 25 cases of female, with an average age of (62.67±8.04) years. The rate of intractable esophageal stenosis in the trial group was lower than that in the control group (6.25% vs. 20.75%, P<0.05). The average endoscopic treatment times in the non-refractory stenosis patients in the trial group were significantly less than those in the control group 〔(1.85±0.27) times vs. (3.24±0.49) times, P<0.05〕, and the occurrence time of esophageal stenosis in the trial group was 51.06 d after ESTD, significantly later than that in the control group (29.12 d, P<0.05). Conclusion Oral corticosteroids can effectively reduce the degree of esophageal stenosis after large area ESTD, as well as the incidence of intractable esophageal stenosis and the number of endoscopic treatment in non-refractory esophageal stenosis patients.