Abstract: OBJECTIVE To explore the effect and mechanism of coptisine on the rat model of chronic renal failure(CRF). METHODS The 60 male SD rats were divided into 6 groups:the blank group, model group, positive control group and the 200,100 and 50 mg·kg^-1 dose of coptisine groups. Rats were gavaged adenine 28 d, except the blank group. The high, middle, low dose of coptisine group rats were gavaged 200, 100 and 50 mg·kg^-1 coptisine each day. After therapy, weight, urinary production and urinary protein in 24 h was detected, urea nitrogen(BUN), creatinine(SCr), TGF-β₁ and PAI-1 in serum was detected by Elisa; the expression of TGF-β₁ and PAI-1 in kidney tissue was detected by Western blot. RESULTS Compared with model group, in 200, 100 and 50 mg·kg^-1 dose of coptisine groups, weight and urinary production of 24 h were increased(P<0.05) and urinary protein in 24 h was decreased(P<0.05); BUN, SCr, TGF-β₁ and PAI-1 level in serum and the expression of TGF-β₁ and PAI-1 protein was decreased(P<0.05). CONCLUSION Coptisine has a certain effect on the renal funtion of CRF rats and its mechanism is related to the expression of TGF-β₁ and PAI-1 in srtum and renal tissue.