The use of endoscopic ultrasonography (EUS) in the diagnosis of submucosal upper gastrointestinal tract lesions was examined in 308 patients. Two-hundred ten submucosal tumors, 89 cases of esophagogastric varices, and 9 cases of non-Hodgkin's lymphoma were found. EUS images were interpreted based upon a five-layer EUS structure of the normal gastrointestinal wall. A characteristic EUS image was seen with leiomyoma, cysts, lipoma, and varices. EUS had an accuracy of 80% in staging nine cases of lymphoma. EUS is a valuable technique for the evaluation and diagnosis of submucosal upper gastrointestinal tract lesions.