The invention relates to a traditional Chinese medicine preparation, in particular to a Chinese patent medicament for treating osteomyelitis and a preparation method. The Chinese patent medicament is characterized by be prepared from the following traditional Chinese medicines in parts by weight: 10-30 parts of rehmannia glutinosa, 10-20 parts of yam, 10-15 parts of dogwood steeping wine, 10-15 parts of Chinaroot greenbrier rhizome, 10-30 parts of tree peony bark, 10-15 parts of rhizoma alismatis, 10-15 parts of placenta hominis and 3-15 parts of golden cypress. The preparation method comprises the following steps of: weighing the raw materials in the weight ratios; preparing the rehmannia glutinosa, the yams and the golden cypress and uniformly mixing, and then pulverizing into fine powder; sieving the fine powder by a sieve of 100 meshes to obtain mixed powder; preparing the dogwood steeping wine, the Chinaroot greenbrier rhizome, the tree peony barks, the rhizoma alismatis and the placenta hominis and adding water to decoct the components twice for 1.5 hours each time; respectively filtering decocting liquors each time and combining filter liquors; heating the combined liquor to 50-70 DEG C and concentrating the liquor into thick paste with a relative density of 1.10-1.30; and finally, mixing the prepared thick paste with the mixed powder, drying, pulverizing, uniformly mixing, granulating, drying and subpackaging. The prepared Chinese patent medicament has definite drug effect, not toxic and side effects, low price and feasible process.