Objectives : In this study, we investigated the effect of methyl gallate of Paeonia suffruticosa(Moutan Cortex Radicis) on inflammatory response in activated macrophages. Methods : RAW264.7 cells were incubated with different concentrations of methyl gallate of Paeonia suffruticosa for 30 min and then stimulated with or without LPS at indicated times. Cell toxicity was determined by MTT assay. The concentrations of nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$) and inflammatory cytokines (TNF-$alpha$, IL-6) were measured in culture medium by Griess assay, enzyme-immuno assay, and ELISA, respectively. The expressions of iNOS, COX-2 and cytokine mRNA and protein were determined by RT-PCR and Western blot, respectively. The $I{kappa}-B{alpha}$ degradation in cytosol and NF-${kappa}B$ p65 translocation into nuclear of the cells were determined by Western blot. Results : Methyl gallate was significantly inhibited LPS-induced production of NO and PGE2 in RAW264.7 cells. Methyl gallate was also suppressed LPS-induced expression of iNOS and COX-2 mRNA and protein in the cells. Methyl gallate was inhibited LPS-induced production of TNF-$alpha$ and IL-6 via suppression of their mRNA expressions. Methyl gallate blocked the NF-${kappa}B$ pathway in LPS-stimulated RAW264.7 cells. Conclusions : This study suggests that methyl gallate of Paeonia suffruticosa may have an antiinflammatory property through suppressing inflammatory mediator production in activated macrophages.