Athyrium niponicum is a species of fern in the genus Athyrium, native to eastern Asia in Japan, northern China, Korea and Taiwan. It is a deciduous herbaceous plant, with whorls of fronds growing from spreading rhizomes. The fronds are 25-40 cm tall and 15-25 cm broad, pinnate, with 6-10 pairs of pinnae 4-9 cm long and 2-3 cm broad, deeply lobed, bright green with a dark red-brown stem in the wild plant, with the spore-bearing sori on the underside of the fertile pinnae. The species name is sometimes cited as "nipponicum".