The invention relates to a traditional Chinese medicine for preventing and treating avian influenza and a preparation method thereof. The traditional Chinese medicine comprises the following traditional Chinese medicinal raw materials: honeysuckle, schizonepeta spike, hedyotis diffusa, astragalus membranaceus, liquorice, radix bupleuri, cyrtomium rhizome, coptidis rhizome, radix isatidis, folium isatidis, herba houttuyniae, herba patriniae, paris polyphylla, rhizoma belamcandae, fructus forsythiae, radix scutellariae, semen armeniacae amarae, fritillary bulb, cortex mori radicis, semen cuscutae, selfheal and chrysanthemum indicum. The traditional Chinese medicinal raw materials are precisely and reasonably mixed, and the traditional Chinese medicine is obtained by cleaning, distilling, preliminary stewing, secondary stewing, mixing, concentration and triple stewing. The traditional Chinese medicine disclosed by the invention is high in absorption speed and obvious in treatment effect, has the effects of clearing away heat and toxicity, realizing antibiosis and diminishing inflammation, can greatly suppress avian influenza, and achieves effects of prevention and treatment; the immunity function of a poultry body is enhanced; meanwhile, effects of better protecting the liver and the kidney are achieved, and the traditional Chinese medicine is suitable for long-time taking.