The invention discloses a medicine for treating bedsore and a preparation method thereof. The medicine is prepared from the following raw material medicines: patrinia, the root of Chinese pulsatilla, long-noded pit viper, potentilla chinensis, Chinese lobelia, liquidambar formosana hance, folium photiniae, azedarach, frankincense, myrrh, caulis spatholobi, hematoxylon, valerian, vines of multiflower knotweeds, polygala tenuifolia, tribulus terrestris, pearls, codonopsis pilosula, astragalus membranaceus, acanthopanax, rhodiola rosea, corn cervi pantotrichum, human placenta, longan aril, radix rehmanniae preparata, red halloysite, cuttlebones, chalcanthite, camphor, apiaries, calomel and calamine. The medicine disclosed by the invention has the beneficial effects that based on the conventional theory of traditional Chinese medicine, the medicine for treating bedsore disclosed by the invention, which mainly invigorates qi and blood and activates blood and promotes granulation, has the advantages of fast effect, good curative effect, high safety, no toxic and side effects and difficulty in replase.