A submucosal bulge of 0.4 cm may be considered for ultrasound gastroscopy, and treatment options may be selected based on the location of the bulge. A submucosal bulge may be caused by a smooth muscle tumor, a lipoma, or a mesenchymal tumor, or it may be caused by a cyst or an extraesophageal tumor compressing the esophagus. The lesion may occur in the submucosal layer of the esophagus, the muscularis propria, and so on. Ultrasound gastroscopy can visualize the layers of the submucosal origin of the esophagus, which may be the lamina propria or the muscularis mucosae. If it occurs in the submucosal or intrinsic muscular layer, endoscopic submucosal dissection can be performed. If it originates in the muscular layer of the mucosa, most require thoracoscopic surgical treatment. For submucosal elevation of the esophagus, if it is less than 2 cm or less, it can also be observed clinically, and gastroscopy is usually repeated once a year or so. Therefore, for a submucosal bulge of 0.4 cm, it is recommended to consult a physician to determine the next step in management.