Crab claw mushroom is a fungus belonging to Pleurotus of Lycopodiaceae. The scientific name of Pleurotus eryngii is Pleurotus eryngii, which is a kind of wood rot fungus. It is native to broad-leaved forest areas such as beech in cold temperate zone, and mostly occurs in autumn. Distributed in temperate regions of the northern hemisphere, including North America, Europe, Siberia, Japan, China and other places. It is rich in nutrition and has high medicinal value.