The invention discloses medicine treating cough and a preparation method thereof. The medicine treating cough is prepared from pears, cassia twigs, Chinese honeylocust fruits, Chinese leek roots, alnus cremastogyne flowers, exocarpium, cherokee rose roots, fivevein meconopsis herb, levant cotton roots, aleppo avens, chimonanthus nitens, eriobotrya japonica, elephantopus scaber, roots of henry currant, myrsinaceae, plantain, sanicula lamelligera hance, affine cudweed, saxifrage, tiny ardisia, folium artemisiae argyi, radix stemonae roots, fleshy lysionotus, denseflower bulbophyllum herb, lacebark pine cones, largeleaf curculigo rhizome, schisandra propinqua, rhizoma imperatae, ciliatenerve knotweed roots, white mulberry root bark, radix aristolochiae, radix et rhizoma ephedrae, loofah sponge, fritillaria, asarum and negundo chastetree fruits. The prepared medicine combines external application and internal use, treats both symptoms and root causes and improves the treatment effect easily, besides, treatment speed is increased easily, and treatment time is saved.