In two patients, frequent retching and vomiting preceded acute upper gastrointestinal hemorrhage. Congestion and edema were limited to the prolapsed portion of the stomach, the cardia, where discrete erosions and small shallow ulcers were seen. At endoscopy, prolapse of the gastric mucosa into the esophageal lumen was quite evident whenever the patients retched. The endoscopic features and pathogenesis of Mallory-Weiss syndrome were readily differentiated. It seemed probable that repeated retching causing intussusception of the cardia of the stomach can mechanically produce gastritis and should be a recognizable cause of acute upper gastrointestinal bleeding. I take this entity to be an independent superficial mucosal disease of the stomach.