Cortinarius cinnamomeus, also known as the cinnamon webcap, is a basidiomycete mushroom of the genus Cortinarius. The fungus produces brown fruit bodies with caps up to 6 cm (2.4 in) wide and stems up to 12 cm (4.7 in) long. The closely crowded gills underside the cap are initially yellow before turning brown. Cortinarius cinnamomeus is common in damp places in coniferous forests. It is distributed throughout the temperate zone of the Northern Hemisphere.