〔Abstract〕 Objective To investigate the effect of mesencephalic astrocyte-derived neurotrophic factor(MANF) on the adaptive expression of bile acid transporter in human hepatoellular carcinomas(HepG2) induced by rifampicin(RFP). Methods The control group cell line(Y07) and the knockdown group cell line(Y25) were constructed by lentiviral stable transfection technology. The Y07 and Y25 cells were treated with RFP of 200 μmol/L for 48 h, and qRT-PCR and Western blot were used to detect the protein and gene expression levels of MANF, bile salt export pump(BSEP), multidrug resistance-related proteins 2/3/4(MRP2, MRP3, MRP4), multidrug resistance protein 1(MDR1), organic solute transporter a/β(OSTα/β), organic anion transporter(OATP2B1). The protein and gene expression levels of proliferating cell nuclear antigen(PCNA), proliferating cell marker Ki67 were used to evaluate the proliferation of cells in each group changes in levels. Changes in the protein and gene expression levels of C/EBP homologous protein(CHOP) and cysteinyl aspartate specific proteinase-3(Caspase-3) were used to evaluate the apoptosis of cells in each group.The relative contents of alanine aminotransferase(ALT),aspartate aminotransferase(AST), alkaline phosphatase(ALP), total bilirubin(TBIL),indirect bilirubin(IBIL)and total bile acid(TBA)in the supernatant of cell culture medium of each group were detected by kits. Results RFP could induce the protein and gene expression of MANF, BSEP, MRP2, MRP3, MRP4, MDR1, OSTα, OSTβ, OATP2B1 in HepG2 cells(P<0.05), while the protein and gene expression levels of BSEP, MRP2, MRP3, MRP4, MDR1, OSTα、OSTβ、OATP2B1 decreased after MANF knockdown(P<0.05). Moreover, under the action of RFP, the protein expression of PCNA and Ki67 in the knockdown group was still higher. The protein and gene levels of CHOP and Caspase-3 significantly increased after MANF knockdown(P<0.05). The levels of the hepatic cell injury markers in the cell supernatant increased significantly(P<0.05). Conclusion RFP can induce the expression of bile acid transporter such as BSEP, MRP2, MRP3, MRP4, MDR1, OSTα, OSTβ and OATP2B1 to increase in HepG2 cells(P<0.05), but the expression of bile acid transporter of HepG2 after MANF knockdown will significantly decrease under the induction of rifampicin(P<0.05),and cell indury is aggravated, indicating that MANF plays a protective role in RFP-induced adaptive responses by regulating the bile acid transporter.