The invention provides use of 5,7-methoxy-3,4'-flavonol in resisting of respiratory tract inflammatory diseases and relates to application of the 5,7-methoxy-3,4'-flavonol in preparation of drugs forresisting the respiratory tract inflammatory diseases. According to the use, proven by a series of experiments, 7-methoxy-3,4'-flavonol has obvious inflammation resisting, oxidation resisting, tracheacontraction reaction resisting activity; absorption can be achieved through oral drug administration, a relatively high drug effect is displayed, the bioavailability is 10% to 25%, and the 7-methoxy-3,4'-flavonol can be prepared into oral application preparations, injections and inhalants. The 5,7-methoxy-3,4'-flavonol can replace glucocorticoid preparations and is applicable to various respiratory tract inflammatory diseases such as bronchial asthma, acute bronchitis, chronic obstructive pulmonary disease, acute / chronic lung injury and respiratory distress and pulmonary fibrosis.