Gymnopus herinkii is a rare species of mushroom-forming fungus in the family Omphalotaceae.

It was described in 1998 by mycologists Vladimír Antonín and Machiel Noordeloos.

The type specimen was from a collection made in the Lenora region of Bohemia, made by Czech mycologists Jiří Kubička and Josef Herink in 1952; the latter is acknowledged in the species epithet.

[2] Marcel Bon proposed a transfer to the genus Collybia in 1998.

[3] Characteristic features of Gymnopus herinkii include the distantly-spaced gills on the underside of the hygrophanous, brown cap, and an onion-like odour.