Disclosed is a novel natural material having an immune balance-regulating activity. Specifically disclosed is an immune balance regulator comprising small glossy black soybean (a bean belonging to the genus Glycinemax), a crushed product of the bean, or an extract of the bean or the crushed product with an aqueous ethanol solution as an active ingredient. The immune balance regulator can activate an immunocyte essential for biophylaxis, particularly an antigen-presenting cell, to activate an immune function. The immune balance regulator can also suppress excess Th2 immunological ability so as to keep a good balance between Th1 immunological ability and Th2 immunological ability, thereby enhancing an immunological biophylaxis function and inhibiting an undesirable allergic reaction.
