The usefulness of endoscopy in marginal ulcer bleeding has rarely been studied, and the optimal method for preventing rebleeding is unclear. Here we assessed the efficacy of endoscopy in marginal ulcer bleeding and examined the efficacy of proton pump inhibitors (PPIs) in the prevention of rebleeding. A total of 28 patients with marginal ulcer bleeding (21 men, 7 women; median age 58.5 years) were treated by endoscopy. We analyzed the clinical characteristics, results of endoscopic therapy, characteristics of rebleeding patients, and relation between the use of PPIs and the duration of rebleeding. Sixteen patients had active bleeding. Initial hemostasis was achieved in all patients. There were no procedure-related adverse events. Rebleeding occurred in one patient within the first month and in 7 patients thereafter. There was a significant difference in the rebleeding rate between the patients who received a PPI and those who did not. In a multivariate analysis, the non-use of PPIs was a risk factor for rebleeding (hazard ratio, 6.22). Therapeutic endoscopy is effective in achieving hemostasis from marginal ulcer bleeding. PPIs may prevent rebleeding from marginal ulcers.