The invention relates to the technical field of traditional Chinese medicines, in particular to a traditional Chinese medicine composition for improving postoperative prognosis of breast cancer and application of the traditional Chinese medicine composition. The traditional Chinese medicine composition consists of the following raw materials in parts by weight of 15-30 parts of radix astragali, 15-30 parts of radix codonopsis, 15-30 parts of rhizoma curcumae, 15-30 parts of herba salviae chinensis, 6-12 parts of radix bupleuri and 9-15 parts of radix paeoniae alba. Aiming at syndrome differentiation and treatment of the breast cancer, all the raw materials and the weight part ratio thereof are preferably selected; the traditional Chinese medicines in a formula conform to the compatibility requirement of monarch, minister, assistant and guide, specifically, the radix codonopsis and the radix astragali are used as monarch medicines for invigorating the spleen and replenishing qi, the rhizoma curcumae and the herba salviae chinensis are used as ministerial medicines for reducing phlegm and removing stasis, the radix paeoniae alba is used as the adjuvant medicine for nourishing yin and soothing the liver, and the radix bupleuri enters the liver channel as the guide medicine; all the medicines are combined for achieving the effects of tonifying qi, strengthening the body resistance, reducing phlegm, removing stasis, soothing the liver and promoting the circulation of qi; and the whole formula combines tonification and purgation and gives consideration to both symptoms and root causes. Experimental results show that the prognosis (including OS, DFS indexes and the like) of a patient treated with the traditional Chinese medicine formula is obviously superior to that of a patient not using the traditional Chinese medicine formula, and the application prospect is wide.