The invention relates to a traditional Chinese medicinal compound preparation for treating deficiency of spleen qi due to stomach cancer and a preparation method thereof. The traditional Chinese medicinal compound preparation is prepared from the following components in parts by weight: 30 to 50 parts of radix codonopsis, 10 to 30 parts of radix ophiopogonis, 6 to 18 parts of fructus schizandrae, 10 to 30 parts of fried bighead atractylodes rhizome, 10 to 30 parts of poria cocos, 10 to 30 parts of poria with hostwood, 10 to 30 parts of folium eriobotryae, 6 to 8 parts of processed pinellia ternate, 10 to 30 parts of caulis perllae, 30 to 50 parts of coix seed, 10 to 30 parts of fructus aurantii, 10 to 30 parts of eriobotrya japonica, 10 to 30 parts of rice sprout, 10 to 30 parts of malt and 3 to 9 parts of liquorice root. The preparation method comprises the following steps: decocting the raw materials, filtering dregs of a decoction, adding white granulated sugar, sodium benzoate and ethyl p-hydroxybenzoate, and stirring for dissolving; boiling; performing hot pressurized sterilization to obtain the traditional Chinese medicinal compound preparation. By adopting the traditional Chinese medicinal compound preparation, the deficiency of spleen qi due to stomach cancer can be treated in order to treat cancer through micro adjustment and balance; a key point is found, and the spleen and stomach are regulated through a small prescription and a small dose in order to strengthen the right and expel the evil, autoimmunity and repairing function of an organism are mobilized by balancing yin and yang as well as vital energy and blood, and the aim of treating stomach cancer is fulfilled.