The invention relates to an externally-applied Zhuang medicine for treating beriberi and skin pruritus and a preparation method thereof, which solves the problem of poor curative effect of the prior medicine. The externally-applied Zhuang medicine is prepared from the following raw materials proportioning by weight: 10-20 of common lantana, 10-30 of yellow-corktree bark, 10-30 of Chinese knotweed,10-30 of perfoliate knotweed herb, 6-18 of wrinkled gianthyssop, 4-12 of radix sileris and 8-22 of artemisia leaf. The medicine can be made into spraying agent, liniment, lotion, film coating agent,aerosol, ointment or tincture in a known method. The preparation method comprises the following steps: pulverizing the seven raw material medicines into coarse powder, carrying out thermal refluxing extraction for 2-4 times by alcohol to the coarse powder to obtain an extracting solution, filtering the extracting solution, merging filtrate, then adding 2-4% of menthol and 2-4% of camphor, standingafter stirring and dissolving, filtering and filling to obtain the liniment. The medicine has the functions of clearing away heat and toxic substances, eliminating dampness and relieving itching. Themedicine can be used for not only treating skin pruritus, beriberi, maculae, pimple, blain, erosion and soakage caused by moist heat, but also treating persons with the symptoms of superficial mycosis infection and mosquito bite. The medicine has the advantages of good and quick curative effect, no side effect and little possibility of relapse.