Two Inonotus species newly found in Japan were described. I. formosanus T.T. Chang & W.N. Chou was identified with the following characters; thin basidocarps with hispid when young and later the erect hyphae agglutinate to scrupose tuft, pore surface light yellow to rusty brown later, absence of setal hyhpae, ventricose hymenial setae, and small ellipsoid, hyaline to yellowish basidiospores. I. nodulosus (Fr.) P. Karst. was identified with the following characters; basidocarps nodulose, wart-like shape, scrupose to warted by agglutinated hayphae, margin up to 5 mm, pore surface cinnamon to rusty brown when dry with a whitish or silvery shine, absence of setal hyphae, acute straight hymenical setae, ellipsoid to subglobose basidiospores, which are weakly dextrinoid in Melzer’s reagent.