This study aims to investigate the effect and specific mechanism of Coix Seed Oil (CSO) on immune hepatic fibrosis in immune injury rats. In this study, healthy Wister rats were injected with porcine serum in order to establish hepatic fibrosis model. We choose the compound Sophora flavescens injection as the positive control drug. HE staining was used to observe the morphological and histological changes. HSC-T6 cells were cultured in vitro. MTT and AO/EB staining were used to detect the effect of CSO on the proliferation and apoptosis of HSC-T6 cells. The results shown that Coix seed oil significantly improved hepatic fibrosis of immune injury rats, and the degree of hepatic fibrosis in CSO group was significantly reduced. Intraperitoneal injection of 15 mg/kg, 30 mg/kg and 40 mg/kg significantly reduced the levels of serum ALT, AST, ALP, HA, LN, PIIINP and C-IV in rats (P < 0.01).), MTT assay showed that the cells proliferated well. The results of HE staining showed that Coix seed oil had a good therapeutic effect on immune-induced hepatic fibrosis in rats. AO/EB staining showed that 0.5 mg/mL CSO for 24 h and 0.1 mg/mL CSO for 48 h both significantly promoted the apoptosis of HSC-T6 cells. In conclusion, Coix seed oil has a significant therapeutic effect on immune hepatic fibrosis, and its molecular mechanism may be related to antagonizing cytokine TGF-β1, inhibiting the expression of TIMP-1, promoting collagen degradation, inhibiting the activation of hepatocyte and promoting the apoptosis of activated hepatic stellate cells.