Objective To observe the protective effect of rosuvastatin on kidney in patients with early-stage diabetic nephropathy. Methods 64 patients with early-stage diabetic nephropathy were randomly divided into the treatment group(n=32) and the control group(n=32). The patients of the treatment group were treated with rosuvastatin (10mg, po, qn) + routine medication, while the patients of the control group were treated with routine medication alone.All patients were treated for 12 weeks.Routine medication included diabetic diet, blood glucose control and anti-hypertensive drugs.Urinary albumin excretion rate(UAER), urinary β2-microglobulin(β2-MG), serum creatinine (Scr), C-reactive protein(CRP), fasting plasma glucose(FPG), low density lipoprotein-C(LDL-C), high density lipoprotein-C(HDL-C), total cholesterol(TC) and triglyceride (TG) were determined and compared between the two groups before and after treatment for 12 weeks. Results 12 weeks after treatment, the levels of UAER, Scr, β2-MG and CRP were lower in the treatment group compared with before treatment[(123.4±10.5)μg/min vs.(85.4±12.6)μg/min, (98.2±11.5)μmol/L vs.(76.3±8.6)μmol/L, (0.76±0.35)mg/L vs.(0.37±0.21)mg/L, (19.5±1.5)mg/L vs.(10.3±1.6)mg/L], the differences were statistically significant(t=3.461, 3.532, 3.284, 3.671, all P<0.05).12 weeks after treatment, the levels of UAER, Scr, β2-MG and CRP in the control group and in the treatment group were (117±12.5)μg/min vs.(85.4±12.6)μg/min, (92.7±8.3)μmol/L vs.(76.3±8.6)μmol/L, (0.69±0.24)mg/L vs.(0.37±0.21)mg/L, (17.7±1.2)mg/L vs.(10.3±1.6)mg/L, there were significant differences between the two groups(t=3.365, 3.584, 3.752, 3.274, all P<0.05). LDL-C, TC and TG were lower in the treatment group. Conclusion Rosuvastatin can improve renal function in patients with early-stage diabetic nephropathy by regulating the levels of blood lipid and decreasing the levels of CRP, UAER and urine protein. Key words: Diabetic nephropathies; Rosuvastatin; Proteinuria