Pharmaceutical compositions for treating immunological disorders and the preparing method of the same are disclosed, which include alcohol extracts of Radix Dioscorea, Rhizoma Alismatis, Poria cocos (schw) Wolf, and Scutellaria Baicalensis. The compositions are manufactured by novel procedures consisting of decocting using specific concentration ranges of alcohol, filtering, regulating pH value, purifying, concentrating, proportionally mixing, and making a granule powder from lyophilized extract. This invention used both in vitro and in vivo assays to evaluate therapeutic effects of specific combination of herbal plant extracts. The combination of herbal extracts has been able to maximize the anti-inflammatory activity and regulate the secretion of cytokines such as eotaxin and IL-4. When the pharmaceutical composition of the present invention is used for asthma, it can relieve coughs, resist airway allergic inflammation reactions, improve the pulmonary functions, reduce allergen specific IgE in bloods, stabilize elasmatoblasts, and stop the attacks from asthma.