The invention relates to a preparation method of traditional Chinese medicine for treating phlegmatic hygrosis type acute bronchitis and belongs to the technical field of preparation methods of traditional Chinese medicine. The phlegmatic hygrosis type acute bronchitis is generally treated by antibiotics and sulfonamides at present, and the disadvantage is that toxic and side effects are high. The preparation method adopts the technical scheme that the preparation method comprises the steps of soaking plumeria rubra, radix isatidis, scabrous elephantfoot herb, polygonum cuspidatum, saxifraga stolonifera, brook anemone, herba patriniae, changium smyrnioides, a largeseed hemsleya root, radix tinosporae, trollflower, honeysuckle, railway beggarticks herb, cordate houttuynia, hyperforin perforatum, sedum sarmentosum, hemianthus micranthemoides, rhizoma picrorhizae, tea, sticktight, herba andrographitis, paris rhizome, Japanese white birch bark, water shield, dayflower, centella asiatica, blackberry lily, remote lemongrass herb, dragonwort, gardenia, rhizoma coptidis, amoorcorn tree bark, broomjute sida herb, airpotato yam, iron holly bark, flos chrysanthemi indici, common alstonia, coffee senna and liquorice in water, decocting with soft fire, filtering and deslagging. Decocted medicine liquor is the traditional Chinese medicine for treating the phlegmatic hygrosis type acute bronchitis. The method has the advantages that the prepared traditional Chinese medicine is low in toxic and side effects and high in cure rate.