The invention relates to a traditional Chinese medicine preparation for treating mastitis and a preparation method. The effective components of the prepared traditional Chinese medicine preparation comprise raw materials: sedum, Chinese usnea, crossostephium chinense, polygonum perfoliatum L, daphne genkwa, sheepear inula her, antlerpilose grass, marsilea quadrifolia, acorn, scorzonera austriaca wild, ainsliaea latifolia, root of fingerleaf morningglory, franchet groundcherry, colocasia konishii hayata, hoya carnosa and lance asiabell root. The traditional Chinese medicine preparation of the invention is prepared by employing a modern advanced medical pharmaceutical technology, and the selected medicinal materials are compatible with each other and accord with theories of traditional Chinese medicine and modern medicine. The traditional Chinese medicine preparation has the efficacies of regulating qi, dispersing nodules, diffusing lactation, freeing the collateral vessels, discharging heat and elevating edema, and has substantially treatment effect on mastitis symptoms such as breast distending pain, acaking and the like for females and especially for lactating women; the traditional Chinese medicine preparation is safe and has no toxic and side effects, and is capable of adjusting endocrine, nourishing qi and blood, and improving human body microcirculation; and the traditional Chinese medicine preparation has important clinical meaning for mastitis treatment, and is worth widely popularizing and applying.