The invention discloses a traditional Chinese medicine preparation for preventing and treating synovitis and a preparation method. The traditional Chinese medicine preparation is prepared from main raw materials in parts by weight as follows: 7-13 parts of cassia twigs, 9-12 parts of Heterophyllous wing seed tree roots, 5-10 parts of Populus nigra var. thevestina, 8-13 parts of debregeasia, 6-12 parts of red peony roots, 3-9 parts of herbs of bastardtoadflax-like swallowwort, 7-12 parts of Chinese lobelia herbs, 5-11 parts of broad-leaved ainsliaea, 4-8 parts of acanthopanax bark, 6-10 parts of Embelia laeta (L.), 9-13 parts of honeysuckle, 3-10 parts of brooklet anemone roots, 6-9 parts of fruit of Chinese wingleaf prickyash and 7-11 parts of Diospyros rhombifolia Hemsl.. The traditional Chinese medicine preparation is safe and free of side effects, has remarkable preventing and treating effects, has lower cost which can be accepted by a patient, has the efficacy of warming and dredging meridians, dispelling wind, dredging collaterals, eliminating dampness, diminishing inflammation, relieving pain, strengthening bones and muscles, dispelling cold, subsiding swelling, promoting blood circulation and removing stasis and can promote local blood circulation, improve surrounding tissue nutrition, promote unblocking of blocked microcirculation and eliminate synovial fluid reabsorbing barriers, the dynamic equilibrium of synovial fluid production and absorption is recovered, finally, the patient recovers thoroughly and is not prone to relapse.