Background. The aim of this study was to compare the effect of high-dose oral rabeprazole versus high-dose IV PPI on rebleeding after endoscopic treatment of bleeding peptic ulcers. Methods. This was a two-center, prospective, randomized, controlled trial. Patients with a high-risk bleeding peptic ulcer had endoscopic hemostasis and were randomly assigned to the high-dose oral rabeprazole group (20 mg twice daily for 72 hours) or the high-dose IV omeprazole group (80 mg as a bolus injection followed by continuous infusion at 8 mg/h for 72 hours). Results. The study was stopped because of slow enrollment (total n = 106). The rebleeding rates within 3 days were 3.7% (2 of 54 patients) given oral rabeprazole and 1.9% (1 of 52 patients) given IV omeprazole (P = 1.000). The rebleeding rates after 3 days were 1.9% and 0% (P = 1.000), respectively. The surgical intervention rates were 3.7% and 0% (P = 0.495), and the mortality rates were 1.9% and 0% (P = 1.000), respectively. Conclusions. The effect of high-dose oral rabeprazole did not differ significantly from that of high-dose IV omeprazole on rebleeding, surgical intervention, or mortality after endoscopic treatment of bleeding peptic ulcers, but this requires further evaluation.