 This study is a randomized, double-blinded, placebo-controlled clinical trial on type 2 diabetic Kidney Disease in early stage microalbuminuria excretion rate 20-200ugmin to evaluate the therapeutic effect of tang shen prescription.632 participants will be recruited for the study, all of whom had type 2 diabetes, serum creatinine concentrations is normal, and no evidence of non-diabetic renal diseases. The study will last for 24 weeks. Subjects will be randomly divided into two groups, either tang shen prescription or placebo,and both of them would be performed on a basic treatment which includes diabetes education, diabetic diet, rational control of blood glucose, and losartan at 50 mg daily, study group take tang wang prescription. Measurements of microalbuminuria excretion rate, albumin-to-creatinine ration, glomerular filtration rate GFR, serum creatinine concentrations will be tested monthly, and quantity of 24h urinary protein per three months. 