The invention discloses a compound traditional Chinese medicine composition for treating poultry respiratory tract infection and a preparation method thereof, and belongs to the technical field of veterinary traditional Chinese medicine. The compound traditional Chinese medicine composition is mainly composed of the following traditional Chinese herbals in parts by weight: 20 to 100 parts of isatis root, 20 to 120 parts of radix scutellariae, 15 to 100 parts of radix astragali, 15 to 100 parts of polygonum cuspidatum, 5 to 20 parts of licorice, and 2 to 10 parts of dihydroxypropyl theophylline; and preferably is mainly composed of the following traditional Chinese herbals in parts by weight: 25 to 75 parts of isatis root, 30 to 90 parts of radix scutellariae, 20 to 60 parts of radix astragali, 20 to 60 parts of polygonum cuspidatum, 5 to 15 parts of licorice, and 2 to 8 parts of dihydroxypropyl theophylline. In the formula, the isatis root has the functions of clearing heat, removing toxicity, cooling blood, and soothing the throat, the radix scutellariae has the functions of clearing heat, drying dampness, purging fire, and removing toxicity, the radix astragali has the functions of preventing bacteria and strengthening the organism immunity, the polygonum cuspidatum has the functions of dissolving blood stasis, relieving pains, stopping coughing, and reducing phlegm, and the licorice has the functions of tonifying the spleen, boosting qi, clearing heat, and removing toxicity. The five traditional Chinese herbals are co-used with dihydroxypropyl theophylline to enhance the effect of the formula on treating poultry respiratory tract infection, and the compound traditional Chinese medicine composition has the advantages of quick effect and prominent curative effect.