The invention discloses a plaster with a function of activating blood to remove stasis and a preparation method thereof. The plaster is prepared from sesame oil, yellow lead, pangolin scales, centipedes, scorpions, pseudo-ginseng, ginseng, cinnamon, radix angelicae pubescentis, notopterygium roots, eucommia ulmoides, radix cyathulae, earthworms, angelica sinensis, monkshood roots, rhizoma arisaematis, kudzuvine roots, ephedra, caulis spatholobi, radix aconiti, borneol, olibanum, myrrh, sangusis draconis, lycopodium clavatum and garden balsam herb. The compound traditional Chinese medicine ozone oil provided by the invention is independently packaged in each bottle with 8-12 g to form a finished product. The plaster provided by the invention has the following greatest advantages: the plaster can dispel wind, eliminate dampness, relieve swelling and pain, promote qi to activate blood circulation, reunite tendons and bones and activate blood circulation to remove blood stasis. The preparation method provided by the invention adopts advanced technologies like ultrafiltration, so the plaster has good appearance color and luster; the content of effective components of the preparation ishigh; and the quality of the preparation is stable and easily-controllable.