The efficacy of H2-blocker and triple therapy in curing duodenal ulcer was compared and the contribution of the eradication of Helicobacter pylori on ulcer remission was assessed. Forty-two duodenal ulcer patients infected with H. pylori were randomized to receive either H2-blocker therapy with famotidine (n = 21) or triple therapy with bismuth, amoxicillin, and metronidazole (n = 21). All patients received treatment for four weeks. Endoscopic evaluation of ulcer status and bacteriologic identification of H. pylori were performed at two, six and 12 months after therapy. Triple therapy had a similarly high healing rate to H2-blocker therapy (100% vs 90.5%) at two months of follow-up. However, at 12 months of follow-up, the ulcer remission rate in the triple therapy group (94.4%) was significantly higher than that of the H2-blocker therapy group (38.9%) (p < 0.05), resulting in the former therapy having a significantly lower rate of H. pylori infection compared to the latter (5.6% vs 100%, p < 0.005). Patients with persistent H. pylori infection at two months of follow-up had a significantly higher ulcer recurrence rate (64.7%) at 12 months than those without infection (5.3%) (p < 0.05). The success of triple therapy in ulcer remission may be attributed to the high eradication rate of H. pylori.