Inocybe hystrix is an agaric fungus in the family Cortinariaceae. It forms mycorrhiza with surrounding deciduous trees. Fruit bodies are usually found growing alone or in small groups on leaf litter during autumn months. Unlike many Inocybe species, Inocybe hystrix is densely covered in brown scales, a characteristic that aids in identification. The mushroom also has a spermatic odour that is especially noticeable when the mushroom is damaged or crushed. Like many other Inocybe mushrooms, Inocybe hystrix contains dangerous amounts of muscarine and should not be consumed.