To investigate the effect of Coptis Chinensis on NF-κB， PPAR-γ and pathological changes of kidney in STZ-induced Diabetic Rats. Methods:Diabetic model in SD rats were established by intravenous injection of STZ combined with high-fat chow feeding. The models were randomly divided into a model group， an Irbesartan group ［31.25 mg/(kg·d)］， and Coptis Chinensis low-， mid-， and high-dose ［equal with Coptis Chinensis used in human:83 mg/(kg·d)，500 mg/(kg·d)，1000 mg/(kg·d)］ groups (n=8 each)， other 8 SD rats were selected as normal group. After 12 consecutive weeks of administration， the expression of NF-κB and PPAR-γ in kidney was detected， and the pathological changes of kidney were observed. Results:The Coptis Chinensis groups decreased the expression of NF-κB (P<0.05); The Coptis Chinensis mid-dose group and Irbesartan group increased the expression of PPAR-γ(P<0.05); In all the Coptis Chinensis groups and Irbesartan group， pathological changes of kidney on STZ-induced diabetic rats were alleviated. Conclusion:Coptis Chinensis can decrease the expression of NF-κB， increase the expression of PPAR-γ and alleviate the pathological changes of kidney in STZ-induced Diabetic Rats.