''Neofavolus alveolaris'' is a species of polypore fungus in the family Polyporaceae. It is widely distributed in the temperate areas of the Northern Hemisphere. Its kidney- or fan-shaped fruit bodies measure 1–8 cm in diameter. Initially reddish, they become cream to white when dry. The pores on the cap underside are angular to hexagonal and relatively large . The fungus causes a white rot in hardwoods.