Electrospinning of 4,4-bishydroxydeoxybenzoin (BHDB)-polyphosphonate was performed by varying polymer concentration, flow rate, and the distance between the charged electrode and the grounded target. High flame-resistant nanofibers with diameters of similar to 100 nm were obtained by spinning from 65 wt % DMF solution. The nanofibers were unimodal in distribution and uniaxially aligned. The heat release capacity and char yield of the BHDB-polyphosphonate nanofibers were 70 +/- 3 J/g K, and 53%, respectively, in close agreement with the values obtained from the bulk materials. Electrospun nanofiber mats of BHDB-polyphosphonate with high flame-retarding properties had good mechanical strength (similar to 95 MPa) and modulus (similar to 3.9 GPa). (C) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 111: 301-307, 2009