The invention relates to the field of medical supplies, in particular to a waterproof compound indomethacin dacronine plaster and a preparation method thereof. The compound indomethacin dacronine plaster includes a waterproof layer, a base cloth layer and a plaster layer in sequence, the waterproof layer includes a first waterproof layer and a second waterproof layer, and first waterproof layers are distributed on both sides of the base cloth layer. layer and the second waterproof layer, the second waterproof layer is between the base cloth layer and the plaster layer, the waterproof layer is a super-hydrophobic surface layer, the plaster layer is a Chinese medicine coating layer, and the base cloth layer is a non-woven cloth. The ointment is based on 100 mass points: 2-3 parts of indomethacin, 0.1-0.3 parts of dyclonine hydrochloride, 7-9 parts of camphor, 3-5 parts of menthol, 29-31 parts of zinc oxide, 22 parts of rosin ‑24 parts, lanolin 3‑5 parts, dimethyl sulfoxide 3‑5 parts, and the rest are rubber. The invention has strong surface hydrophobicity, is not easy to be attached by dirty stains, and has strong air pollution prevention ability.