Dieulafoy's lesion also known as exulceration simplex with submucosal arterial malformation is a rare cause of massive upper gastrointestinal hemorrhage with high mortality. Surgery that has been considered as the preferred diagnostic and therapeutic option has been supplemented by endoscopy; gastroscopy may be a valid alternative for diagnosis and therapy. Between 1981 and 1988 we report 4 cases with massive upper gastrointestinal hemorrhage, haematemesis and hemodynamic decompensation consistent with Dieulafoy's lesion. In all patients emergency gastroscopy was performed, monopolar electrocoagulation was successfully applied in two patients. One patient died during surgery and another sixteen days after surgery from multiple organ failure. Rebleeding was seen in one of the coagulated patients, the site of bleeding was identified as Dieulafoy's lesion in three patients during the first endoscopy and was arterial spurting with normal surrounding gastric mucosa. All lesions were found in the upper third of the stomach. Diagnosis is not easy, especially when the bleeding is intermittent but once identified, endoscopic treatment should be attempted and if this fails surgery may be promptly performed with possible lowering of mortality.