In managing patients with bleeding peptic ulcers, it has been reported that pharmacologic treatment can be an alternative to endoscopic treatment. We compared the hemostasis rates of the endoscopic treatment, hemoclipping, and the phamacologic treatment, oral proton pump inhibitors (PPIs), in bleeding peptic ulcer. A randomized prospective study was performed on 129 bleeding peptic ulcer patients with hematemesis or melena. Sixty-two patients were treated by endoscopic hemoclipping and subsequently H₂ receptor antagonists were injected intravenously (hemoclipping group), and 67 patients were treated with an oral PPI without endoscopic treatment (PPI group). The 24-hr gastric pH test was performed sequentially following the treatment. The initial hemostasis rate of the hemoclipping group was 93.5% (58/62) and the rebleeding rate was 6.9% (4/58), and the hemostasis rate of the PPI group was 92.5% (62/67) and the rebleeding rate was 7.5% (5/67), which were not different. The 24-hr gastric pH was 4.54 ± 2.56 in the hemoclipping group and 5.97 ± 1.30 in the PPI group (P < 0.037). In the bleeding peptic ulcer patients, the hemostasis rate with the oral administration of PPIs was not different from that with the endoscopic hemoclipping treatment.