Objective:To optimize the program for prevention and treatment of renal insufficiency of diabetic nephropathy （DN） and to evaluate the effectiveness and safety of the program of TCM treatment based on syndrome differentiation for protection of renal function.Methods:With method of randomized

blind

controlled and multi-central clinical study

221 cases of renal insufficiency of DN were divided into group A （TCM treatment based on syndrome differentiation group）

group B （Losartan group） and group C （TCM treatment plus Losartan treatment group）.The treatment course was 3 months.Results:After treatment

the increasing amplitude of serum creatimine clearance rate （Ccr） in group A was higher than in group B（P<0.05）

and the decreasing amplitude of serum creatimine（SCr） in group A was higher than in group B（P<0.01） and C（P<0.05）;There was no significant difference in blood urea nitrogen （BUN） and 24-hour urinary protein among the 3 groups（P>0.05）.After treatment of 3 months

serum alanine aminotransferase（ALT）

electrocardiogram（ECG） and B-ultrasonic examination results of the liver

gallbladder

spleen and pancreas did not have significant change（P>0.05）[WTBZ] with on significant difference among the 3 groups（P>0.05）.[WTHZ]Conclusion:The TCM treatment program in addition to diet regulation

decreasing blood sugar and expectant treatment is effective and safe in improving renal function

and the program is better than Losartan in increasing Ccr and decreasing SCr.