The invention discloses a medicinal preparation for treating oral lichen planus. The medicinal preparation is composed of the following raw materials in parts by weight: 10 to 60 parts of peach seed, 5 to 50 parts of phellodendron, 5 to 50 parts of raw rehmannia root, 5 to 50 parts of safflower, 3 to 30 parts of Chinese yam, 3 to 30 parts of Chinese angelica, 3 to 30 parts of achyranthes root, 3 to 30 parts of balloonflower root, and 3 to 30 parts of radix bupleuri. The medicinal preparation has the advantages of novel formula, simple composition, low cost, prominent effect, no side or toxic effect, and difficult generation of drug resistance, and has a good curative effect on oral lichen planus.