The invention provides a traditional Chinese medicine composition for treating periodontitis. Any common dose form can be prepared from prepared rehmannia root, rehmannia, spatholobus stem, human placenta, fortune's drynaria rhizome, uniflower swisscentaury root, red sage root, Chinese magnoliavine fruit, Chinese yam, curcuma tuber, milkvetch root, achyranthes root, wild chrysanthemum flower, Poria cocos, wolfberry, tree peony bark, oriental waterplantain rhizome and cassia bark by using a conventional preparation method of modern preparation technology. The invention also relates to application of the traditional Chinese medicine composition in preparation of drugs used for treating weak teeth due to sourness, feeble chewing, loosening and shifting of teeth, swelling gums, gringival hemorrhage and chronic periodontitis caused by kidney vacuity and excessive internal heat. The traditional Chinese medicine composition has the advantages of capacity of simultaneous treatment of principal and subordinate symptoms, good safety, a good curative effect, convenient usage, etc.