A feeling of food retention in the esophagus indicates the presence of dysphagia. Dysphagia is a sensation of obstruction and stagnation in the pharynx, retrosternum, or xiphoid process, which is the obstruction of the transportation of food from the oral cavity to the stomach and cardia. It may be associated with reflux esophagitis, esophageal cancer, pancreatic achalasia and other diseases. 1. Reflux esophagitis: mainly power dysphagia, caused by diffuse esophageal spasm and stenosis due to long-term inflammation of the lower esophagus, resulting in dysphagia. Patients mainly manifest acid reflux, heartburn, retrosternal pain and difficulty in eating and swallowing. 2. Esophageal cancer: mainly mechanical dysphagia, caused by narrow lumen due to tumor growth, but also due to the weakening or disappearance of esophageal peristalsis caused by infiltration of the wall by the cancer, resulting in dynamic dysphagia. The main manifestations of patients are weight loss, retrosternal pain and progressive dysphagia. 3. Cardia dysphagia: It is power dysphagia caused by the weakening of ganglion cells in the intestinal muscle plexus, and it is mostly related to mental factors. Patients mainly show that they need to drink a lot of water when eating to help dry food swallowing, and there are symptoms of regurgitation in the later stage. If dysphagia occurs, it is recommended to consult a doctor as soon as possible for detailed investigation, to clarify the cause of the disease and to carry out active and effective treatment.