Abstract: The maggots of Musca domestica were bathed in different temperatures of water，and the change of antioxidant activity was measured. The results showed that antioxidant activity had no significant change bathing at 50℃，while that at 80℃ and 100℃ had significant decline in a short time，then remained stable，which suggested that housefly bots have high temperature resistant antioxidant material. The maggot extracts were bathed at 100℃ for different time，and the antioxidant activity was measured to screen antioxidant material with thermostability. The results showed that the residual antioxidant substances after treatment at 100℃ for 5 min，could remain stable at 50℃，80℃， 100℃ for 5 h，even under the condition of 120℃ for 30 min. Comprehensive analysis combined with SDS-PAGE electrophoresis and trichloroacetic acid precipitation showed that the antioxidant material was a 30 ku peptide.