Abstract： Objective： To explore the protective effect of Bushen Jiedu decoction on radiation- induced infectious lung injury. Methods：72 C57BL/10J mice were randomly divided into blank control group，simple irradiation group，amifostine group and traditional Chinese medicine group， with 18 mice in each group. The mouse models of each group were established. On the 11th day after the beginning of the experiment，the mice in blank control group did not receive irradiation， and the other mice in each group received one-time 6 Gy 60Co γ 30 min before the whole body irradiation with fostine. Six mice in each group were randomly selected on the 1st ， 7th and 14th day after irradiation. The lung coefficient was calculated. Procalcitonin(PCT)， C- reactive protein(CRP) and interleukin- 6(IL- 6) were detected by enzyme- linked immunosorbent assay(ELISA)，and the pathomorphological changes of mouse lung were observed under optical microscope. Results： On the first day after irradiation， the lung coefficient of the blank control group was lower than that of the other three groups(P＜0.05)， and that of the simple irradiation group was higher than that of amifostine group and traditional Chinese medicine group(P＜0.05). On the 7th day after irradiation， the lung coefficient level in the blank control group was lower than that in the simple irradiation group and amifostine group(P＜0.05)，while that in the simple irradiation group was higher than that in the amifostine group and traditional Chinese medicine group(P＜0.05). On the 14th day after irradiation，the lung coefficient in the simple irradiation group was higher than that in the other three groups(P＜0.05).The pathomorphological changes were the most obvious in the simple irradiation group. Amifostine group and traditional Chinese medicine group could significantly reduce the pathological changes of lung tissue， and the traditional Chinese medicine group was better than amifostine group. On the first day after irradiation， the levels of PCT， CRP and IL- 6 in the blank control group were significantly lower than those in the other three groups(P＜0.05)，while the levels of CRP and IL- 6 in the simple irradiation group were higher than those in amifostine group and traditional Chinese medicine group(P＜0.05). On the 7th day after irradiation，the levels of PCT，CRP and IL-6 in the blank control group were lower than those in the other three groups(P＜ 0.05)， those in the simple irradiation group were higher than those in the amifostine group and the traditional Chinese medicine group(P＜0.05)，and those in the traditional Chinese medicine group were lower than those in the amifostine group (P＜0.05). On the 14th day after irradiation，the levels of PCT and IL-6 in the blank control group were lower than those in the simple irradiation group and amifostine group(P＜0.05)， higher than that in the amifostine group and traditional Chinese medicine group(P＜0.05)，lower than that in the amifostine group(P＜0.05)，and the level of CRP in the simple irradiation group was higher than that in the other three groups(P＜0.05). Conclusion：Bushen Jiedu decoction can reduce the infection degree of radiation-induced lung injury，reduce the levels of PCT and CRP，and play an anti-inflammatory and anti-injury role.