02PS15 extracts (BuOH, $H_2O$, and crude extracts) significantly inhibited IL-4 and IL-6 secretion from the phytohemagglutinin (PHA)-plus phorbol 12-myristate 13-acetate (PMA)-induced peripheral blood mononuclear cleas (P<0.05). 02PS15 extracts (BuOH and crude extracts) also significantly inhibited the histamine release from rat peritoneal mast cells (P<0.05). Significant reduced levels (P<0.05) of PMA- and A23187-induced IL-8 were observed in the human mast cell line, HMC-1, with O2PS15 extracts (BuOH and crude extracts). 02PS15 extracts (BuOH and crude extract) downregulated the expression of IL-6 and IL-8 in the activated HMC-1. These results suggest that O2PS15 has the inhibitory effect of atopic allergic reaction anil this might be useful for clinical application to treat several allergic diseases such as atopic dermatitis.