The susceptibility of allergic rhinoconjunctivitis (ARC) patients to air pollution has yet to be clarified.Based on a repeated measurement panel study, we explored the association of short-term PM exposure with lung function in ARC patients and to further identify the susceptible populations.Personal PM exposure, including PMShort-term PM personal exposure was associated with a significant decrease in lung function in ARC patients, especially for small airway respiratory indexes. The highest estimates occurred in PMThese novel findings estimated the short-term effects of PM on lung function in ARC patients, and the threshold values of IgE for the significant and robust associations.