Objective: Fibroblast growth factor 21(FGF21) is an important metabolic regulator and is expressed predominantly in the liver. In this study, we evaluate the role of LY2405319, an analogue of FGF21 in hepatic stellate cells (HSCs) activation and methionine and choline-deficient (MCD)-diet induced mouse model of liver fibrosis. Methods: Male C57BJ6 mice, 6-to 8-weeks-old were fed with the MCD diet (MCD diet group) as an animal model of NAFLD, or control chow diet (control group) for 8 weeks. All mice, which were fed their assigned MCD diet for 8 weeks, were randomized into two groups on the end of 4 weeks of MCD diet feeding and then the LY2405319, a FGF21 analog, (1.5 mg/kg/day; n = 8) or PBS solution (control MCD group; n = 8) were injected subcutaneously daily for 4 weeks with simultaneously another 4 weeks of MCD diet feeding. Results: Palmitate or MCD medium treatment increased succinate concentration of LX-2 cells (HSCs) and enlarged production of GPR91 and α -SMA. However, LY2405319 administration ameliorates palmitate or MCD media-induced escalated succinate production and over-expression of GPR91 and α-SMA in LX2-cells. In vivo study, the MCD diet treatment showed increased steatohepatitis and liver fibrosis compared with the control diet in mice. LY2405319 administration improved steatohepatitis and ameliorated GPR91 and α -SMA overexpression in the liver of MCD diet- induced mouse model. These results show that FGF21 reduces α-SMA production by inhibiting succinate-GPR91 pathway. Conclusion: In conclusion, FGF21 acts as an inhibitor of the succinate-GPR91 pathway to control liver fibrosis. FGF21 has the therapeutic potential for treating liver fibrogenesis.