To meet the demand of high ignition energy in narrow space, a new energetic composite was prepared compounding high-energy Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(HNIW) into macroporous polyacrylonitrile(PAN) fibrosa by electrostatic spinning(ES) method and self-assembly method. The morphology, thermal property and combustion behavior of as-prepared composite were analyzed by SEM, FT-IR, thermal analysis and combustion residues analysis. Results show that HNIW is uniformly distributed on the fibrosa; their compound is a physical process; there is no chemical change. Compared with pure PAN fibrosa, the addition of HNIW enhances the combustion performance of fibrosa, and initial exothermic temperature of HNIW shifts about 38 ℃ downwards because of the existence of fiber. The fiber and HNIW can completely react in a particular proportion.