In the present study, effects of essential oils isolated from various plants have been evaluated on lipopolysaccharide (LPS)-induced release of nitric oxide (NO), prostaglandin E$_2$(PGE$_2$) and tumor necrosis factor-a (TNF-$alpha$) by the macrophage RAW 264.7 cells. Among the tested essential oils, essential oil of Ligularia fischeri var. spiciformis (LF-oil) significantly inhibited the LPS-induced generation of NO, PGE$_2$ and TNF-$alpha$ in Raw 264.7 cells. Consistent with these observations, the expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 enzyme was inhibited by LF-oil in a concentration-dependent manner. Thus, this study suggests that inhibition of release of iNOS, COX-2 expression, and TNF-$alpha$ by the essential oil of Ligularia fischer may be one of the mechanisms responsible for the anti-inflammatory effects of this medicinal plant.