Background: Acute upper gastrointestinal bleeding (UGIB) is a common gastrointestinal disease emergency and a cause of morbidity and mortality. Objectives: To assess the clinical outcomes and explore predictive factors for mortality of elderly patients with acute UGIB. Methods: During the study period from January 2010 to September 2011, we prospectively enrolled 981 patients presenting with UGIB from 11 hospitals (mean age ± standard deviation (SD), 59.4 ± 14.9 years; range, 17−94 years; including 661 men). Of these 981 patients, 499 (50.9%) were elderly. Basic demographic data and clinical findings, and Rockall scores were collected and calculated. Results: We studied 499 elderly patients. Their mean age ± SD was 71.63 ± 7.65 years. The 30-day mortality rate was 9% and rebleeding was just 1%. Regression analysis showed a pulse rate >100 beats per min at first visit, red blood in a nasogastric aspiration, comorbidity with coronary artery disease, and creatinine >1.5 mg/dL were independent predictive factors of 30-day mortality. Conclusions: Peptic ulcer bleeding is a major cause of acute UGBI in the elderly. We recommend patients with predictive factors of mortality, pulse rate >100 beats per min at first visit, red blood in nasogastric aspiration, comorbidity with coronary artery disease, and creatinine >1.5 mg/dL be closely monitored and treated promptly. Reducing mortality from peptic ulcer bleeding should focus on preventing peptic ulcer occurrence as a result of ulcerogenic medications.