The inventors have found that vitamin K3 and vitamin K5 which may be used in pharmaceuticals and foods or ACNQ, DHNA, or the like which can stimulate the growth of bifidobacteria can inhibit degranulation of basophil-like cells, exhibit a potent degranulation-inhibiting effect, and are useful anti-allergic agents or foods. The present invention provides an anti-allergic agent containing, as an active ingredient, one or more species selected from among 2-amino-3-carboxy-1,4-naphthoquinone, 1,4-dihydroxy-2-naphthoic acid, 1,4-naphthoquinone, 4-amino-2-methyl-1-naphthol, 2-methyl-1,4-naphthoquinone, 2-amino-3-chloro-1,4-naphthoquinone, and a salt thereof.