Cortex Mori (Moros alba L.), the root bark of mulberry tree has been used as an autiphlogistic, diuretic and expectorant in herval medicine. Recently, a few papers reported that phenolic extract of Cortex Mori had the hypotensive, hypoglycemic, antiviral and anticancer effects, and hot water extract of Cortex Mori(CM) had inhibitory effect on the degranulation and histamine release from activated mast cells. These previous studies suggest a possibility that CM has an antidotal activity against inflammation which was mediated mainly by macrophage-secreting inflammatory factors. This study was performed to evaluate the influences of CM on carrageenan-induced edema in vivo and release of inflammatory mediators such as NO, TNF and IL-1 by macrophages stimulated with LPS or $IFN-{gamma}$ in vitro. Subcutaneous injections of carrageenan into the mouse paw rapidly induced local edema by increasing vascular permeability, but single intraperitoneal injection of CM extract at 30 minutes before carrageenan suppressed the development of edema. NO and TNF production from macrophage stimulated by LPS or $IFN-{gamma}$ were significantly suppressed, especially TNF secretion by up to 3-4 folds. LPS stimulated IL-1 production was also inhibited, but not significantly. Cell viability assay verified that the inhibition was not due to general cell toxicity. These results suggest that reduction of NO, TNF and IL-1 production may be one of the means by which CM prevent inflammation associated diseases.