〔Abstract〕 Objective To explore the protective effect and mechanism of salvianolic acid salt on acute lung injury induced by one lung ventilation(OLV) in rabbits. Methods 24 rabbits were randomly divided into three groups: control group, model group and treatment group, with 8 rabbits in each group. The W/D value of lung was measured, and the morphological changes of lung tissue were observed by HE staining and electron microscopy; The contents of arachidonic acid(AA),leukotriene B4(LTB4),thromboxaneA2(TXA2) and prostacyclin 2(PGI2) in rabbit lung tissue were detected by ELISA; The expressions of cyclooxygenase-2(COX-2),5-lipoxygenase(5-LOX) in lung tissue were detected by RT-qPCR; The expressions of COX-2, 5-LOX, clara cell secretory protein(CCSP)and cytoplasmic phospholipase A2(C-PLA2) in lung tissue were detected by Western blot. Results The W/D ratio of model group was higher than that of control group, but decreased after treatment(P<0.05); HE staining showed that in the model group, the capillaries were dilated and congested, there were red exudates in the alveoli, the walls of alveoli were thickened, and inflammatory cells were infiltrated, but the treatment of salvianolic acid salt was relieved; The mitochondria swelling, crista breaking and even disappearing were observed by transmission electron microscope in the model group, and alveolar epithelial cell Ⅰ(AT-Ⅰ) ultrastructural damage in the treatment group significantly improved compared with that in the model group; The AA, LTB4, TXA2 and PGI2 contents in the treatment group were lower than those in the model group(P<0.05). RT-qPCR showed that the expression of COX-2 and 5-LOX in model group was higher than that in control group(P<0.05), while the expression of COX-2 and 5-LOX decreased after Salvianolic acid salt treatment(P<0.05); Western blot showed that the expression of COX-2, 5-LOX and C-PLA2 in treatment group was lower than that in model group, while the expression of CCSP increased(P<0.05). Conclusion Salvianolic acid salt has protective effect on lung injury induced by one-lung ventilation. Its mechanism may be related to down-regulation of COX-2, 5-LOX and C-PLA2 expression, up-regulation of CCSP expression.