The invention discloses a traditional Chinese medical external-use powder, in particular a traditional Chinese medical external-use powder for treating children pulmonitis and a preparation method thereof. The traditional Chinese medical external-use powder for treating children pulmonitis is characterized in that the powder is prepared from the following components of peach kernel, tatarian aster root, white mulberry root-bark and bulbus fritillariae cirrhosae. The traditional Chinese medical external-use powder is specially used for treating the children pulmonitis; a plurality of medicinesare properly mixed, the curative effect is improved by utilizing the synergy effect or the resistance effect of the medicines so that the traditional Chinese medical external-use powder meets the treatment requirements of complex disease states, and the adverse reaction is reduced. The traditional Chinese medical external-use powder is convenient to take, has the characteristics of less drug dosage, good curative effect, short period, cheap price, no side effect and the like and has a better curative effect on the children pulmonitis. In 1580 treatment cases, the total effective rate reaches 98%.