The rhizome of Atractylodes japonica Koidzumi (AJK) has been used in traditional medicine for treatment of arthritis, bronchitis and respiratory infectious disease, whereas its effects on inflammatory reactions have not been unknown recently. In this study, the effects of AJK on allergic inflammation and its signaling were investigated in the induced human mast cells and animal model. This study showed that ethanol extract of AJK interestingly suppressed the production and mRNA expression of TNF-${alpha}$, IL-6 and IL-8, as important inflammatory cytokines. Furthermore, AJK inhibited the nuclear translocation of nuclear factor (NF)-$kappa$B through inhibition of the phosphorylation of I$kappa$B-${alpha}$, which was additionally elucidated by NF-$kappa$B promoter-mediated luciferase activity. In addition, the phosphorylation of ERK was increased in pretreatment with AJK, whereas there was no change in JNK and p38 MAPK. However, AJK showed no effects on anti-DNP IgE-mediated in vivo PCA reaction and histamine release, as key events of mast cell-mediated immediate allergic reactions. These results suggest that AJK might be involved in not early-phase but transition to late-phase reactions of allergic inflammation and could modulate through other signal pathways. Taken together, AJK could be used as a treatment for mast cell mediated late-phase/chronic allergic inflammatory reactions.