Objective:To study the express of HO-1 on acute inflammation induced by LPS and the anti-inflammatory effect of the melilotus suaveolens extract.Methods:Inflammatory cell model was constructed by LPS acting RAW264.7 cell line.The expression of mRNA and protein of Hemeoxygenase 1(HO-1)were detected by real-time PCR and Western blot method.Results:The expression of HO-1 mRNA in macrophage cell was significantly enhanced by the melilotus suaveolens extract.The result of Western blot showed that the expression of HO-1 protein was significantly increased after the intervention of melilotus suaveolens extract.Conclusion:The melilotus suaveolens extract can resist inflammation by enhancing the expression of HO-1.