Abstract: OBJECTIVE To study the effect of glycyrrhizin acid and osthole on the treatment of alcoholic fatty liver in rats， and to explore the mechanism of compatibility of components. METHODS After the establishment of rat alcoholic fatty liver， the rats were randomly divided into normal group， model group， positive drug group (Lipingzhi)， osthole (Ost) group， glycyrrhizic acid (GL) group， high dose group of osthole and glycyrrhizic acid， medium dose group of osthole and glycyrrhizic acid and low dose group of osthole and glycyrrhizic acid. The treatment groups were given by gastrogavage every day starting from the 5th week， the positive group ig. Lipingzhi 20 mg/(kg·d)， the osthole group ig. Ost 10 mg/(kg·d)， the glycyrrhizic acid group ig. GL 22.5 mg/( kg·d)， the low dose group ig. the compatibility components of Ost 5 mg/(kg·d) and GL 11.25 mg/(kg·d)， the medium dose group ig. Ost 10 mg/(kg·d) and GL 22.5 mg/(kg·d)， the high dose group ig. Ost 20 mg/(kg·d) and GL 45 mg/(kg·d) and the normal and model group were given distilled water with equal volume for 6 weeks. We observed the sign of rats， the pathological changes of liver with the optical microscope. Then we measured AST， AKP and ALT changes in rat serum and TC， TG， SOD and MDA contents in liver homogenate. The expression of PPARα protein in liver tissue was examined using Western blot method. RESULTS Compared with the model group， the pathological changes of liver tissue were improved in different treatment groups and the ALT， AST and AKP levels in serum were significantly decreased in the groups of glycyrrhizin combined with osthole at medium and high doses(P<0.05). The liver tissue of rats test results showed the medium dose and high dose groups of glycyrrhizin combined with osthole could significantly reduce the content of MDA and improve the activity of SOD. There were significant differences among the model group and the treatment groups at medium and high doses (P<0.01). The TG and TC levels in the group of glycyrrhizin combined with osthole in medium dose were lower than the model group(P<0.05). Western blot results showed that the PPARα protein levels in treatment groups compared with the model group had a different degree of increase， and the compatibility of medium dose and high-dose groups in the liver tissue of PPARα protein expression was up-regulated with statistical significance (P<0.01). CONCLUSION The reasonable combination of glycyrrhizic acid and osthole had synergistic treatment on alcoholic fatty liver， and its main mechanism might be related to the improving of liver function， regulation of fat metabolism， anti-lipid oxidation and the increased protein expression of PPARα.