Mycena atkinsoniana is a species of agaric fungus in the Mycenaceae family. It is one of the so-called "bleeding mycenas" that will ooze yellow to orange juice when injured. Other distinguishing features include the upper stem surface that is decorated with tiny purplish-brown fibers, and the gills, which are pale yellow with maroon edges. The reddish-brown caps are smooth with a grooved margin, and up to 3 cm (1.2 in) wide. Mycena atkinsoniana is known from the United States and Canada, where it grows scattered or in groups on leaf litter in forests during the summer and autumn. It was originally described from collections associated with beech, but it is also frequently found under eastern North American oaks.