Effect of soybean hydrolysate prepared by ultrafiltration(UF-peptide) was evaluated regarding its action on blood pressure, selected biochemical changes in spontaneously hypertensive rats(SHR). Male SHR were divided into three groups and fed diet with 0, 3, 10% UF-peptide for 6 weeks. Development of hypertension was determined by tail cuff method during the experimental period. After the experimental period, angiotension I converting enzyme(ACE) activity in serum and vascular tissue, and lipids level in serum were measured. Spontaneous elevation of blood pressure was suppressed by the UF-peptide supplementation after two weeks of feeding. After five weeks of feeding the development of hypertension was significantly inhibited in the UF-peptide administered groups compared to the control. In addition, the UF-peptide was effective for lowering serum lipids level such as triglyceride and total cholesterol, as well as ameliorating some pathological changes in SHR.