Severe asthma is difficult to treat because it involves neutrophilic inflammation that is unresponsive to corticosteroids rather than eosinophilic inflammation. Recently, it has become clear that ferroptosis, an iron-dependent cell death, is involved in various diseases. In respiratory diseases, it is becoming clear that smoking induces ferroptosis and is involved in COPD and asthma severity. In this study, we investigated the involvement of ferroptosis in the exacerbation of airway inflammation in a mouse model of papain-induced asthma. Iron deposition in lung tissue was not observed in the papain alone-exposed group but was significantly increased in the co-exposed to papain and tobacco smoke (TS) or erastin, ferroptosis inducer, groups. The number of neutrophils and eosinophils in mice in BALF co-exposed to papain and TS/erastin was significantly increased compared to that in the papain alone-exposed group, especially the number of neutrophils was significantly increased in the TS group. These profiles provide new insights into the exacerbation of airway inflammation in severe asthma.