This prospective follow-up study was designed to analyze the causes and outcome of upper gastrointestinal bleeding among patients presenting by hematemesis and/or melena to Emergency Endoscopy Unit, Ain Shams University Hospitals. One thousand patients presented by upper GIT bleeding were subjected to complete clinical evaluation, emergency upper gastrointestinal endoscopy and therapeutic interventions as indicated. Follow up was done for occurrence of re-bleeding or mortality. Variceal causes of bleeding were the most common, representing 70.1% followed by non-variceal causes (26.1%) and obscure causes (3.8%). Esophageal varices (EV) alone represented 17.8% of causes of variceal bleeding, while combined esophageal and gastric varices represented 39.5% and isolated gastric varices 12.8%. Gastric lesions were the most common causes of non variceal bleeding. Recurrence of bleeding occurred in 19.4% of variceal group in comparison to 6.1% of non variceal group, while mortality was found in 4.3% of variceal group in comparison to 1.5% of non variceal group with very highly significant difference (P <0.001). Hypertension, ascites, EV columns, EV grade IV, presence of gastric varices and associated respiratory disorder were independent factors associated with recurrence of bleeding in variceal group. In non variceal group, recurrence of bleeding was significantly related only to the presence of gastric ulcers (P=0.035). Independent factors associated with mortality in studied patients were age, associated diabetes, presence of esophageal varices and associated duodenal ulcer.