Bjerkandera fumosa is a species of poroid fungus in the family Phanerochaetaceae.

[1] Petter Adolf Karsten transferred the species to the genus Bjerkandera in 1879.

[2] The form of Bjerkandera fumosa fruit bodies ranges from effused-reflexed (spread out over the substrate and turned back at the margin to form a cap) or cap-like, but attached directly to the substrate without a stipe.

The pores on the cap underside are circular to angular, numbering 2–5 per millimetre.

[3] Bjerkandera fumosa has a monomitic hyphal system, containing only generative hyphae.