Abstract: OBJECTIVE To explore the regulation effect of conciliatory antiallergic decoction on TLR3 and NF-κB/IRF3 signaling pathway in allergic asthma mice induced by respiratory syncytial virus(RSV). METHODS BALB/c mice were randomly divided into control group, model group, dexamethasone group(0.5 mg·kg^-1), conciliatory antiallergic decoction low, medium and high dose groups(17.5, 35.0, and 70.0 g·kg^-1), with 10 mice in each group. Asthma model was established by RVS combined with ovalbumin sensitization. Twenty-four hours after the last challenge, airway resistance was examined via mice exposing to vaporized methacholine. Mice was anesthetized and broncho-alveolar lavage fluid was prepared. Then the inflammatory cells including macrophages, eosinophils, lymphocytes and neutrophils were counted, the contents of IgE, CD31, IL-4, TNF-α and MPO were detected. Lung tissues injury were evaluated with HE staining, TLR3 expression in lung tissues was determined with immunohistochemical staining, and the mRNA expression of TLR3, NF-κB and IRF3 in lung tissues were detected with qRT-PCR. RESULTS Compared with the model group, the airway resistance in all dose of conciliatory antiallergic decoction groups were significantly inhibited, the lung tissues injury and inflammatory cell infiltration were also attenuated, the counts of macrophages, eosinophils, lymphocytes and neutrophils were significantly decreased, the contents of IgE, CD31, IL-4, TNF-α and MPO in broncho-alveolar lavage fluid were also decreased. The expression of TLR3, NF-κB and IRF3 in lung tissues were also decreased. CONCLUSION Conciliatory antiallergic decoction has treatment effect against asthma induced by virus, this may related to the regulation of TLR3/NF-κB/IRF3 signaling pathway.