The invention discloses a method for establishing an animal model with opportunistic infections and chronic wasting diseases, and a traditional Chinese medicinal preparation for treating opportunistic infections and chronic wasting diseases. The traditional Chinese medicinal preparation is prepared by the following components in parts by weight: 100-180 parts of monkhood, 100-180 parts of dry ginger, and 100-160 parts of liquorice. The method has the positive effects that the method for establishing the animal model with opportunistic infections and chronic wasting diseases is found, and the model has high controllability, reliability and repeatability, and is convenient and economical to use; the model syndrome accords with the attack process of opportunistic infections and chronic wasting diseases; the model establishing factor accords with the theory of the Internal Canon of Medicine, and does not relates to causal organisms, so that the testing risks can be reduced, and the organism safety can be guaranteed; the traditional Chinese medicinal preparation obtained by screening has the characteristics of high efficiency, no toxicity, wide medicine sources and the like, is convenient to use and economical, can be used for prolonging the life of patients with opportunistic infections and chronic wasting diseases, improving the living quality of the patients and improving lesion of each tissue, and does not have toxic or side effect when a large dosage is used.