The present invention addresses the problem of providing an agent for ameliorating allergy that has an effect of inhibiting the secretion of an inflammatory cytokine and thus ameliorating disorders in the immunoregulatory system in vivo, and products for ameliorating allergy such as foods, drinks, feeds and medicines, said products containing the agent for ameliorating allergy. An agent for ameliorating allergy which comprises, as an active ingredient, a galactooligosaccharide having a structural formula: O-&bgr；-D-galactopyranosyl-(1&rarr；6)-[O-&bgr；-D-galactopyranosyl-(1&rarr；4)]-D-glucose； or O-&bgr；-D-galactopyranosyl-(1&rarr；4)-[O-&bgr；-D-galactopyranosyl-(1&rarr；6)]-D-glucose.
