The mesoscopic structures of TATB(1,3,5-triamino-2,4,6-trinitrobenzene)-based PBXs(polymer bonded explosive)and their time evolutions were investigated using the dissipative particle dynamics(DPD)method.The results show that most of the polymers are condensed to spheres and only several polymer chains extend into TATB,the polymers form reseau structure in TATB.TATB is fixed in the polymers,but can not be wrapped perfectly by the polymers.At the same time,with the increasing of the temperature and the content of the polychlorotrifluoroethylene(PCTFE)monomers in the polymer,more polymers are dispersed in TATB.When the temperature is up to 400 K,the polymers form the alveolate structure,and wrap TATB perfectly.