Abstract： Objective To investigate the effects of triptolide on diabetic nephropathy (DN).Methods Seventy-five patients of type 2 diabetes with DN of Ⅲ stage were randomized into two groups.Fourty patients in treatment group received triptolide 60 mg/d and losartan 100 mg/d,while the other 35 patients in control group received losartan 100 mg/d; with a course of 12 weeks in each group.The levels of 24 h urine albumin,laminin (LN),ⅣV-collagen(C-Ⅳ),high sensitive C-creative protein (hsCRP) and urinary podocytes were measured before and after the treatments.Results After 12 weeks of treatment,the levels of 24h urine albumin,LN,C-Ⅳ,hsCRP,and urinary podocytes in two groups decreased significantly (P ＜ 0.05) ; the level of LN and hsCRP in treatment group decreased more than that in control group(P ＞0.05) ; the level of 24 h urine albumin,C-Ⅳ and urinary podocytes in treatment group decreased more significantly than that in control group (P ＜ 0.05).No serious adverse reactions occurred in both groups.Conclusions Triptolide may decrease the amount of proteinuria of diabetic nephropathy and in DN developing.The mechanism appears to be related with suppressing expressions of inflammatory cytokines.