A new biflavone, 5'''-hydroxyamentoflavone, was isolated, together with naringenin, apigenin, luteolin, 2, 3-dihydroamentoflavone, amentoflavone, afzelin, cosmosiin, quercitrin, and 4-β-D-glucopyranosyloxyferulic acid, from pollen grains of Cryptomeria japonica D. DON.
