There are three physiological strictures in the esophagus: the first is at the entrance of the esophagus, about 12-15 cm from the incisors, which is often the most common location due to food entrapment. The second physiological stricture is at the sternal angle, 25-27 cm from the incisors, which is the most common cause of esophageal carcinoma and is also the result of compression at the aortic arch and tracheal bifurcation. The third physiological stricture is the lower part of the esophagus, the junction of the esophagus and the stomach, which is the location of the cardia, and is prone to the manifestation of pancreatic cancer of the esophagogastric fundus. The three physiological strictures of esophagus need to pay more attention to the clinical symptoms, such as pain behind the sternum, which is usually more obvious in the second physiological stricture, especially in the early stage of esophageal cancer, most of which are manifested in the second physiological stricture.