Objective: To explore the protective effect and mechanism of Guipi Tang on acute liver injury reduce by ethanol extract from Tripterygium wilfordii in rats.Method: Totally 50 rats were randomly divided into control group

T.wilfordii model group

large-dose

medium-dose and small-dose groups of Guipi Tang（4.5

9

18 g·kg-1）groups.Each group was respectively perfused with the corresponding dose of drug for 5 days.Then T.wilfordii by Ethanol was perfused for 3 days to produce the mode 1.The pathological tissue of liver was detected.The serum levels of alanine aminotransferase（ALT）

aspartate aminotransferase（AST）

superoxide dismutase（SOD）

malondiadehyde（MDA） and glutathione peroxidase（GSH-Px） were measured.Result: Compared with the control group.The serum levels of SOD and GSH-Px in model group decreased and MDA increased obviously（P<0.05）.Pathological investigation showed that liver cell steatosis was took place with cell turbid.Compared with model group

Guipi Tang of all doses could effectively decrease ALT

AST and MDA level

increase GSH-Px level（P<0.05）.Large-dose and medium-dose also increased SOD level（P<0.05）.The liver injury was alleviated.Conclusion: Guipi Tang has effect of protecting the liver and the mechanism of liver injury has a relationship with lipid peroxidation.