Background: Clara cell 10-kDa protein (CC10) is a multifunctional protein with anti-inflammatory and immunomodulatory effects. Induction of CC10 expression by gene transfection may possess potential therapeutic effect. Nuclear factor kappa B (NF-kappa B) plays a key role in the inflammatory processes of airway diseases. Method/ Results: To investigate potential therapeutic effect of CC10 gene transfection in controlling airway inflammation and the underlying intracellular mechanisms, in this study, we constructed CC10 plasmid and transfected it into bronchial epithelial cell line BEAS-2B cells and CC10 knockout mice. In BEAS-2B cells, CC10's effect on interleukin (IL)-1 beta induced IL-8 expression was explored by means of RT-PCR and ELISA and its effect on NF-kappa B classical signaling pathway was studied by luciferase reporter, western blot, and immunoprecipitation assay. The effect of endogenous CC10 on IL-1 beta evoked IL-8 expression was studied by means of nasal explant culture. In mice, CC10's effect on IL-1 beta induced IL-8 and nuclear p65 expression was examined by immunohistochemistry. First, we found that the CC10 gene transfer could inhibit IL-1 beta induced IL-8 expression in BEAS-2B cells. Furthermore, we found that CC10 repressed IL-1 beta induced NF-kappa B activation by inhibiting the phosphorylation of I kappa B-alpha but not I kappa B kinase-alpha/beta in BEAS-2B cells. Nevertheless, we did not observe a direct interaction between CC10 and p65 subunit in BEAS-2B cells. In nasal explant culture, we found that IL-1 beta induced IL-8 expression was inversely correlated with CC10 levels in human sinonasal mucosa. In vivo study revealed that CC10 gene transfer could attenuate the increase of IL-8 and nuclear p65 staining in nasal epithelial cells in CC10 knockout mice evoked by IL-1 beta administration. Conclusion: These results indicate that CC10 gene transfer may inhibit airway inflammation through suppressing the activation of NF-kappa B, which may provide us a new consideration in the therapy of airway inflammation.