Abstract: This paper is to investigate the effect of mild hypothermia on acute radiation syndrome in mice. Forty male BALB/c mice were randomly are divided into 4 groups. The mice were exposed to gamma ray at6.0 Gy,0.92 Gy/min, the mice in mild hypothermia+radiation group were receivedmild hypothermia treatment before irradiation and radiation+mild hypothermia group after irradiation. The descend range of pripheral blood leukocyte number in mild hypothermia+radiation group was 1 week in advance to restore; Thymus weightand coefficient increased, the ratio of PCE/(PCE+NCE) was lower than radiation group.The descend range of pripheral blood leukocyte number in radiation+mild hypothermia group was lower than radiation group on the first day after irradiation, and 4 days in advance to restore. The descend range of pripheral blood leukocyte number in mice treated by mild hypothermia either before or after irradiationdecreased lower in early time after irradiation and recovery earlier, Mild hypothermia had some protective effect on mice radiated at 6 Gy.

Key words: Mild hypothermia, Acute irradiation, BALB/c mice