Inflammatory reaction is characterized by over-production of inflammatory mediators due to an up-regulation of inflammatory pathways, which produce pro-inflammatory mediators, such as interleukin-1beta (IL-$1{eta}$), IL-6, tumour necrosis factor alpha (TNF-$alpha$), prostaglantin $E_2$ ($PGE_2$), and nitric oxide (NO) in U937 cells. We investigate the anti-inflammatory effects of water extracts from Lonicerae Flos and Scutellariae Radix in lipopolysaccharide (LPS)-stimulated U937 cells. Each extract suppressed the production of inflammatory mediators (NO, IL-$1{eta}$, TNF-$alpha$, and $PGE_2$) and the expression of inducible NO synthase and cyclooxygenase-2 in LPS- stimulated U937 cells in a dose-dependent manner. These suppressive effects were synergistically increased by their combination. Their combination extract also inhibited NF-${kappa}B$-DNA complex of NF-${kappa}B$ binding activity and translocation of NF-${kappa}B$ from cytosol to nucleus. These results suggest that the combination of water-extractable components of Lonicerae Flos and Scutellariae Radix may be useful for therapeutic drugs against inflammatory immune diseases, probably by suppressing the production of inflammatory mediators.