Abstract: OBJECTIVE To investigate the potential roles of Toll like receptor(TLR) in pathogenesis of asthma inflammation, and the expression of TLR 3 and 9 in rat asthma model. METHODS The rats were randomly and averagely divided into asthma, control and budesonide-treated group. Expressions of TLR3 and TLR9 protein were detected by immunohistochemical method. RESULTS Expressions of TLR3 protein in lung tissure in asthma group(optical density: 0.201±0.034) and in budesonide-treated group(optical density: 0.195±0.043) were significantly higher than that in control group(optical density: 0.144±0.039)(all P <0.05). While there was no significant difference of TLR3 protein expression between budesonide-treated and asthma group. Dramaticly, expressions of TLR9 protein in lung tissure in asthma group(0.236±0.022 optical density) and budesonide-treated group(optical density: 0.231±0.023) were significantly lower than that in control group(optical density: 0.271±0.025)(all P <0.05). Moreover, there was no significant difference of TLR9 protein expression between in budesonide-treated and asthma group. Furthermore, there was no significant correlation between levels of TLR3 and TLR9 in lung tissue( n =26, r =-0.153, P >0.05). CONCLUSION Level of TLR3 increased in asthmatic asthma lung tissue group. On the other hand, level of TLR9 decreased. TLRs may act as an important role in asthma exacerbation, and the anti- inflammation function of TLRs may not mainly work through TLR3 and TLR9 path way.