Sparassis crispa (SC, Hanabiratake), an edible mushroom which contains beta (1 --> 6) branched beta (1 --> 3) glucan in large quantities, was studied on its immunomodulative effect. As a result, (1) Tumor size of sarcoma 180-bearing mice was smaller than that of control group after 5 weeks by oral administration of SC, and thus their survival was prolonged. (2) By administering SC orally, a blood IgE level and scratching index of NC/Nga mice, which had been induced dermatitis by a continuous application of hapten, were decreased. (3) Human NK cell cytotoxicity was enhanced by oral administration of SC without increasing the number of NK cell. These results suggest that oral administration of SC activates Th1 cell, and inhibits Th2 cell activation, thus promotes a shift in the Th1/Th2 balance toward Th1-dominant immunity.