Objective To observe the possible mechanism of Biejiajian Pill (BP) in fighting a- gainst hepatic fibrosis of hepatic stellate cell T6 ( HSC-T6) by studying effect of BP containing serum on inhibiting proliferation and inducing apoptosis of HSC-T6. Methods Forty Wistar rats were randomly di- vided into the negative control group (NC) , the positive drug control group (P) , high, middle, and low dose groups (H, M, L) , 8 in each group. BP suspension was administered by gastrogavage to rats in Group H, M, L at 21. 87, 43. 75, and 87. 50 mg/mL, respectively. Rats in Group NC were administered with equal volume of normal saline. Rats in Group P were administered with 0. 01 mg/mL colchicine solu- tion by gastrogavage. Each rat received 2 mL corresponding solution, twice per day, with an interval of 12 h gastrogavage, a total of 7 successive times to prepare drug containing serum. HSC-T6 cells were then randomly divided into drug containing serum groups (group H/M/L/NC) , colchicine positive control group (group P) , and the blank control group (BC). Cells in Group H/M/L/NC/P were fed with correspond- ing drug containing serums, while those in-Group BC were cultured with free drug serum. The proliferation inhibition rate of HSC-T6 was detected using CCK8 method at 24, 48, and 72 h, respectively. The apop- totic rate and cell cycle were detected using flow cytometry. Protein expressions of B cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) were detected using Western blot. Results Compared with Group NC, 24-h proliferation inhibition rate of HSC-T6 was obviously elevated in Group M, H, P (P < 0. 05). Compared with Group NC, 48- and 72-h proliferation inhibition rate of HSC-T6 was obviously ele- vated in Group L, M, H, P (P <0. 05). But there was no statistical difference in 24-, 48-, and 72-h prolif- eration inhibition rate of HSC-T6 among Group L, M, H, P (P >0. 05). Compared with Group NC and BC, early-and late-stage apoptosis rates of HSC-T6 obviously increased in Group M, H, P (P<0. 05) ; G,/G1 phase cell number obviously increased in Group M, H, P (P <0. 05) ; S phase and G2/M phase cell num- bers obviously decreased in Group L, M, H, P (P <0. 05). There was no statistical difference in Bcl-2 protein expression among each group (P>0. 05). Compared with Group NC, Bax protein expression ob- viously increased Group L, M, H, P (P <0. 01). Conclusion The mechanism of BP for fighting against hepatic fibrosis might be associated with inhibiting proliferation of HSC-T6 and inducing apoptosis.