Bismuth quadruple therapy is recommended as a first-line treatment for Helicobacter pylori infection in the United States but hybrid therapy is an alternative option. Reverse hybrid therapy (proton pump inhibitor plus amoxicillin for 14 days, and clarithromycin plus metronidazole for the initial 7 days) is a simplified hybrid treatment. We aimed to assess the efficacies of reverse hybrid therapy vs bismuth quadruple therapy as first-line treatments for patients with H pylori infection in a randomized trial. In a prospective study, patients with H pylori infection were randomly assigned to groups that received either reverse hybrid therapy (n = 176) or a bismuth quadruple therapy (pantoprazole, bismuth, tetracycline, and metronidazole for 14 days; n = 176). Patients were examined the end of therapy for adverse events. The study was performed from August 2015 through February 2017. The primary outcome was cure of H pylori infection, determined based on a negative result from the urea breath test, or negative results from histologic analysis, the urease test, and bacterial culture analyses. H pylori infection was eradicated from 96.6% of patients who received reverse hybrid therapy and 96.0% who received bismuth quadruple therapy-this difference was not significant in the intention-to-treat analysis (95% CI, 8.0% ∼ 2.2%; P = .281). There were no significant differences between therapies eradication of clarithromycin-resistant strains (88.2% with reverse hybrid therapy vs 92.3% with bismuth quadruple therapy) or metronidazole-resistant strains (100% vs 96.9%). However, reverse hybrid therapy was associated with fewer adverse events (18.7% of patients) than bismuth quadruple therapy (47.7%) (P < .001). In a randomized trial, we found 14-day reverse hybrid therapy to not be inferior to bismuth quadruple therapy as a first-line treatment for H pylori infection. Reverse hybrid therapy was associated with fewer adverse events. ClincialTrials.gov no: NCT02547038.