Antioxidant activities of 80% ethanol extracts of 63 species of mushroom fruiting bodies were investigated. The ethanol extracts from Daedalea dickinsii, Armillariella mellea, and Fomitella fraxinea showed markedly inhibition on lipid peroxidation in rat liver microsome. The extracts from Daedaleopsis tricolor, Trametes suaveolens, Armillariella mellea, Trichaptium abietinum, Daedalea dickinsii, Fomitella fraxinea, Tylophilus neofelleus, Boletellus obscurecoccineus, and Xerocomus subtomentosus significantly inhibited the hepatic aldehyde oxidase activity, and the extracts from Daedaleopsis tricolor, Armillariella mellea, Daedalea dickinsii, and Fomitella fraxinea slightly stimulated the hepatic SOD activity. These results suggest that Daedalea dickinsii, Armillariella mellea, and Fomitella fraxinea contain the bioactive substances for natural antioxidant and may be useful for development of antioxidant from mushrooms.