Objective To explore the impact and possible mechanism of Yiqi Huayu Jiedu Formula（ 益气化瘀解毒复方

YHJC） combined with ultra-low frequency electromagnetic field treated water（ frequency spectrum water for short） on endotoxin induced rats’ acute lung injury（ ALI）. Methods One hundred and four SD rats were randomized into 13 groups

8 rats in each group. In prevention trial

the prevention frequency spectrum water group

the prevention frequency spectrum water combined with high-dose herb group

the prevention frequency spectrum water combined with low-dose herb group

the prevention common water group

the prevention common water combined with high-dose herb group and the prevention common water combined with low-dose herb group were given corresponding aqueous solution 2 ml by gavage once every day. After 14 days

other groups except the prevention control group were given endotoxin 5 mg / kg by intraperitoneal injection to establish ALI models. In therapeutic trial

other groups except the control group were established models with the same method as in prevention trial. After modeling

the frequency spectrum water combined with high-dose herb group and the common water combined with high-dose herb group were given high-dose herb frequency spectrum water and common water 2 ml by gavage once. Xuebijing（ 血必净） injection（ 4. 5 ml/kg） was given Xuebijing group by intraperitoneal injection once. Microscopic lung pathology and histopathological light microscopic examination were carried out in both trials. The content of serum interleukin 8（ IL-8） and tumor necrosis factorα（ TNF-α） were detected. Results In prevention trial

compared with the prevention control group

IL-8 and TNF-α in the prevention model group increased（ P < 0. 05）. Compared with the prevention model group

IL-8 and TNF-α in the prevention common water combined with low-dose herb group

the prevention common water combined with high-dose herb group

the prevention frequency spectrum water group

the prevention frequency spectrum water combined with low-dose herb group and the prevention frequency spectrum water combined with highdose herb group decreased（ P < 0. 05）. Compared with the prevention frequency spectrum water combined with lowdose herb group

IL-8 and TNF-α in the prevention frequency spectrum water combined with high-dose herb group decreased（ P < 0. 05）. In therapeutic trial

compared with the control group

IL-8 and TNF-α in the model group increased（ P < 0. 05）. Compared with the model group

IL-8 and TNF-α in the frequency spectrum water combined with high-dose herb group

the common water combined with high-dose herb group and the Xuebijing group decreased（ P < 0. 05）. Compared with the frequency spectrum water combined with high-dose herb group

IL-8 and TNF-α in the common water combined with high-dose herb group increased（ P < 0. 05）. Conclusion YHJC had prevention effect on endotoxin induced ALI. It might relate to reducing rats’ serum IL-8 and TNF-α. High-dose herb was more effective. Frequency spectrum water combined with herb compound might strengthen the effect of anti-inflammatory and anti-ALI.