Mycena strobilinoides, commonly known as the scarlet fairy helmet, is a species of agaric fungus in the family Mycenaceae. It is found in North America, where it fruits scattered or in dense groups on needle beds and moss. The mushroom is more common in western than eastern North America, and it prefers to grow at elevations greater than 2,500 feet (760 m) in montane locales. It has amyloid, ellipsoid spores measuring 7–9 by 4–5 μm.