The invention provides a pharmaceutical composition for treating 
spleen deficiency and a preparation method thereof. Based on parts by weight, the preparation method of the pharmaceutical composition comprises the following steps of: mixing 3-5 parts of 
ginseng, 3-5 parts of dangshen, 5-10 parts of 
astragalus membranaceus and 15-25 parts of angelica, and adding 
ethanol for extracting; mixing 15-25 parts of radix paeoniae alba, 8-13 parts of 
pericarpium citri reticulatae, 8-13 parts of 
elecampane, 8-13 parts of yam, 8-13 parts of 
hyacinth bean, 8-13 parts of licorice, 15-25 parts of 
ligusticum wallichii, 5-10 parts of cinnamon, 1-3 parts of rattletop, 1-3 parts of 
radix bupleuri, 1-3 parts of fructus alpiniae oxyphyllae, 1-3 parts of Sichuan pepper,1-3 parts of monkshood, 1-3 parts of rhizoma zingiberis and 10-15 parts of dogwood, and adding pure water for extracting; mixing 15-25 parts of poria cocos, 15-25 parts of bighead atractylodes 
rhizome and 5-10 parts of 
cassia twig, adding 
cellulose, extracting through water, inactivating the extracting solution for later use, mixing the extracting solutions, carrying out vacuum 
freeze drying to obtain 
solid dry paste of a 
drug extract, and carrying out 
superfine grinding and 
pelletizing to prepare the necessary pharmaceutical composition. The pharmaceutical composition provided by the invention is scientific in formula, suitable for 
mass production, free of untoward effect, strong in 
potency, quick to become effective and convenient to take.