Objective To observe the effect of Losartan on proteinuria in the patients with diabetic nephropathy. Method 42 patients with type II diabetes mellitus patients in early-stage diabetic nephropathy were conducted into two groups. 23 patients were treated with losartan

50 mg per day for 24 weeks

19 patients in control group. Results In treating group

proteinuria were significantly reduced from 116±81 μg/min to 50±38 μg/min（p<0.05） as compared with the control group（p<0.05）. Conclusion Losartan is an effective and safe drug for treating early-stage diadetic nephropathy.