OBJECTIVE: Myocardial inflammation during myocardial infarction (MI) could be inhibited by regulating arachidonic acid (AA) metabolism. Recent studies demonstrated that Sini Decoction (SND) was identified to be an effective prescription for treating heart failure (HF) caused by MI. But the anti-inflammatory mechanism of SND remained unclear. The work was designed to investigate the anti-inflammatory mechanism of SND through the AA metabolism pathway METHODS: An inflammatory injury model of H9c2 cells was established by lipopolysaccharide (LPS)-stimulated macrophage-conditioned medium (CM). The MI model was built by the ligation of left anterior descending (LAD) branch of coronary artery in rat. Meanwhile, the rats were divided into five groups: sham group, MI group, MI + Celecoxib group, MI + low-dose SND group (SND-L) and MI + high-dose SND group (SND-H). Cardiac function, histopathological changes and serum cytokines were examined four weeks later. Western blot analysis was conducted to verify the key enzymes levels in the AA metabolic pathway, including phospholipase A2 (PLA2), cyclooxygenases (COXs) and lipoxygenases (LOXs). RESULTS: These CONCLUSION: SND may be a drug candidate for anti-inflammatory treatment during MI by regulating the multiple targets in the AA metabolism pathway.