The exact role of vascular compression of the duodenum to peptic ulcer disease remains unknown, although a review of the literature indicates that the association is more than coincidental. Three patients who had operations for peptic ulcer incurred severe gastric retention. Detailed studies disclosed compression of the duodenum beneath the superior mesenteric vessels. Relief of symptoms followed reoperation in each patient. Apparent gastric atony after vagotomy and pyloroplasty may be an occasional manifestation of vascular compression of the duodenum.