The invention provides an externally used medicine for expelling wind and clearing away cold, activating meridians to stop pain and a preparation method thereof. The medicine is prepared by 25 types of medicinal materials such as radix aconiti preparata, wild aconite root, nux vomica (processed), epimedium, achyranthes root, notopterygium root, cyrtomium fortunei, phellodendron, zaocys dhumnade, hairy antler, dipsacus root, dark plum, asarum, Chinese ephedra, cassia twig, safflower, acanthopanax, honeysuckle, earth worm, loranthus, licorice, drynaria (scald), anisetree bark, myrrh gum (processed) and red ginseng. The medicine links closely with pathogen and pathogenesis of a disease and a plurality of medicines are compatible reasonably, thus expelling wind and clearing away cold as well as activating meridians to stop pain. As an externally used cataplasm, the medicine is taken through skin, thus avoiding the irritation of an oral preparation to gastrointestinal tract; in addition, relatively slow percutaneous absorption process inevitably greatly mitigates drug toxicity to the whole body. Neither skin sensibility nor skin irritation occurs. Therefore, the transdermal drug delivery of new preparation improves the safety of medicine taking to a certain extent and provides new choices for safe clinical medicine use.