The plastic bonded explosive(PBX) based on TATB has been aged 120 days at 0,-10,-20,-30,-40 ℃ respectively. The characteristics of the molecular structure have been identified by FTIR. The thermal stabilities of PBX before and after aged by low temperature have been determined by VST, TG and DTA. The results show that the structure of PBX based on TATB does not change after aged by low temperature, and the thermal stability is good. It declares that low temperature aging has little effect on PBX based on TATB.