Objective To explore the change of the total level of lgE and specific allergen for acute exacerbation of bronchial asthma and to offer evidence for the prevention and cure of acute exacerbation of bronchial asthma.Methods The usual inhalant and ingested antigens were chosen in asthma patients,and the allergens were detected by ELISA in sera of acute exacerbation of bronchial asthma patients.Results Total positive rate of lgE was 92％ (48/52),dust mites 61.2％ (25/52),house dust 17％ (9/52),shrimp and crab 15％ (8/52),mould 9％ (5/52).Conclusion The main allergen of acute asthma exacerbation is dust mites.House dust,shrimp and crab,and mould folloo.The rats of pollen or weed are very low.