The molecular mechanism of how airway inflammation develops is not fully understood. Withaferin A (WA) is a natural phytochemical isolated from the plant Withania somnifera. It is a well-investigated bioactive compound that possesses a variety of health-promoting effects, including anti-inflammatory and anti-oxidative activities. In the present study, the effect of WA on ovalbumin (OVA)-induced airway inflammation in mice was investigated. The results indicated that pre-treatment with WA inhibited OVA-induced lung injury and fibrosis progression in mice. Furthermore, WA significantly downregulated inflammatory cell infiltration into the bronchoalveolar lavage fluid and significantly reduced pro-inflammatory cytokine expression in the lung tissue specimens. Additionally, WA significantly suppressed transforming growth factor-b1 expression in lung tissues. WA also caused the downregulation of collagen I, collagen III, α-smooth muscle actin and tissue inhibitor of metalloproteinase-1, as well as SMADs and extracellular signal related kinase 1/2 inactivation. Notably, WA significantly reduced the activation of the NLRP3 inflammasome. The results indicate that WA may be an effective novel candidate for the treatment of airway inflammation.