Objective To observe the mechanism of Siwu Decoction （Decoction of four ingredients） on blood deficiency syndrome.Methods Wistar rats were randomized into 3 groups: model group

treatment group

and normal group

6 ones in each. Rats of the model group and the treatment group were injected 2% acetylphenylhydrazine （APH） saline subcutaneously on the first

forth and seventh day. From the forth day

the model group was treated with saline by gavage

the treatment group was treated with Siwu Decoction by gavage

and the normal group was treated with saline for 7 days in succession. Then the amount of peripheral blood cells

wet weight of liver and spleen were detected. Liver mitochondrial proteome of all rats were extracted. Proteomic technology was used to measure the regulated proteins by Siwu Decoction.Results In the model group

the rats had decreased general status significantly such as pale

enlarged liver and spleen

lowered red blood cells （RBC） and hemoglobin （HGB）

increased white blood cells （WBC） and reticulocyte （RCT） （P<0.01）

and these changes were recovered quickly after treatment with Siwu Decoction

the 14 changed proteins related to energy metabolism were improved to a certain degree after treatment.Conclusion Siwu Decoction can improve the blood deficiency status at molecular level through regulating liver mitochondria

removing the free radicals and peroxides

stabilizing the mitochondrial structure

preserving mitochondrial functions

and improving carbohydrate

fat and protein metabolism.