To evaluate whether eradication with omeprazole and amoxicillin results in a reduction of ulcer recurrence and rebleeding in patients with Helicobacter pylori-associated duodenal ulcer hemorrhage, patients with upper gastrointestinal hemorrhage from duodenal ulcers with stigmata of recent hemorrhage, a drop in hemoglobin level of more than 2 g/dL, and documented H. pylori infection (by rapid urease test and histologic findings) were randomly assigned to receive omeprazole, 40 mg every day, and amoxicillin, 1 g twice a day, (Group A) or omeprazole alone, 40 mg every day, (Group B) for 2 weeks. No maintenance antiulcer therapy was given. Patients underwent a second endoscopy 4 weeks after completion of therapy and were followed for 1 year. Endoscopy was performed again at the end of 1 year. All patients showed ulcer healing 4 weeks after completion of therapy. H. pylori eradication rates were 83% (Group A) and 5% (Group B) (p < .001). Ulcer recurrences were significantly lower in Group A (3/29 or 10%) than in Group B (9/22 or 41%; p < .05). Comparison of Group A patients with eradication and Group B patients without eradication also revealed a significant difference in rates of ulcer relapse (1/24 or 4% versus 9/21 or 43%; p < .01). Rebleeding occurred significantly less often in the dual therapy group than in the omeprazole group (0/29 versus 6/22 or 27%; p < .01). Eradication of H. pylori significantly reduces the rates of ulcer recurrence and rebleeding in patients with duodenal ulcer bleeding. Dual therapy with omeprazole and amoxicillin should be considered in all H. pylori-positive patients with hemorrhage from duodenal ulcers.