Biscogniauxia is a genus of fungi in the family Xylariaceae. Subtaxa include Biscogniauxia capnodes var. capnodes, Biscogniauxia marginata and Biscogniauxia nummularia, which are plant pathogens. The genus was circumscribed by Otto Kuntze in Revis. Gen. Pl. 2 on page 398 in 1891.