The invention belongs to the technical field of traditional Chinese medicine and discloses external-use medicine for treating beriberi and a preparation method thereof. The external-use medicine comprises, by weight, 12-15 parts of rhizoma chuanxiong, 26-30 parts of radix angelicae dahuricae, 30-35 parts of radix sileris, 10-20 parts of asarum, 15-20 parts of mentha haplocalyx and 5-10 parts of borneol. The external-use medicine has the advantages that the external-use medicine is evident in curative effect on the beriberi, the effective rate of the external-use medicine reaches 100%, the external-use medicine can take effect on the same day when the external-use medicine is used, and the symptoms of the beriberi are relieved even eliminated when the external-use medicine is continuously used for a week; the locally-acting external-use medicine can avoid a liver first-pass effect and kidney burden, is safe, reliable, free of side effects when being used for a long time, capable of improving foot environments, capable of effectively inhibiting and eliminating fungi, viruses and bacteria, economical, practical, convenient to use and fragrant, and does not affect normal movement at all.