The investigators define rebleeding during admission and within 30 days as primary end points. Rebleeding is defined as the one of the clinical manifestations occurring 6 hours after allocation: 1.hematemesis or bloody stool 2. tarry stool and hemodynamic change (systolic pressure less than 90 mmHg, or heart more than 110 beats per minute ) 3. decrease of Hb more than 2g/dl within 24 hours after elevation of Hb to 10 g/dl with transfusion. The investigators define surgical intervention for ulcer bleeding, transfusion amount and hospitalization days after allocation as secondary end points.