Objectives : In this study, the effect of Dipsaci Radix(DR, Dipsacus asperoides C.Y. Cheng et T. M. Ai) water extract on LPS-induced inflammatory response in RAW264.7 cells were investigated. Methods : Dried roots of DR was extracted with water for 3 h(DR-W extract). RAW264.7 cells, a mouse macrophage line, were incubated with different concentrations of DR-W extract for 30 min and then stimulated with LPS at indicated times. Cell toxicity was determined by MTT assay. The concentrations of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) were measured by Griess assay and enzyme immunoassay (EIA), respectively. The expression of inducible nitric oxide synthease (iNOS) and cyclooxyganase (COX)-2 mRNA and protein was determined by RT-PCR and Western blot, respectively. Results : DR-W extract was significantly inhibited LPS-induced productions of NO and PGE2 in RAW264.7 cells. DR-W extract was not suppressed the expressions of iNOS mRNA and protein in LPS-stimulated RAW264.7 cells. Conclusions : This study suggests that DR-W extract can attenuate inflammatory response via inhibition of the NO and PGE2 production in activated macrophages.