Objective To study the effect of Pinus yunnanensis on acute alcoholic liver injury in rats and explore its mechanism. Methods A model of acute alcoholic liver injury in mice was prepared by alcohol. The mice were randomly divided into normal control group, model group, positive control group, Pinus yunnanensis low-, medium-and high-dose groups. Mice in the medicine group were given the corresponding medicine by gavage once a day for 7 days. After the last three hours of intragastric administration, the liver and spleen index, ALT, AST and GSH in serum, SOD, MDA and NO in liver homogenates were measured. Histopathological changes of liver were observed by HE staining. Results Compared with model group, Pinecone of Pinus unnanensis high-, medium- and low-dose groups could significantly reduce the liver index in mice (P<0.01), and high dose groups could significantly reduce the number of spleen (P<0.01); The contents of AST in the medium- and high-dose groups significantly decreased (P<0.01) and the GSH activity significantly increased (P<0.05, P<0.01). There was no significant difference in serum ALT level, SOD activity, GSH activity and NO content in the liver tissues of Pinus yunnanensis groups (P>0.05). HE staining results showed that, the damage of liver tissue in mice of Pinus yunnanensis was significantly improved compared with the model group. Conclusion Pinus yunnanensis has protective effects on acute alcoholic liver injury in mice.