We propose an efficient strategy based on the electrospinning technique combined with multi-dimensional fillers to fabricate composites with well-established thermal pathways. A bridge-type structure is constructed in the composite fibers by integrating 1D boron nitride nanofibers and 2D boron nitride nanosheets, which can accelerate the formation of a valid thermal network, thereby the BNNS/BNNF/polyacrylonitrile (bsf) composites perform better than the BNNS/polyacrylonitrile (bs) composites. This strategy can be extended to the preparation of other electrospun 1D/2D nanofiller/polymer composite fiber films.