ObjectivesThe purpose of this study is to investigate the lung function in Chronic Rhinosinusitis (CRS) patients with Chronic Cough (CC). MethodsA total of 1413 CC patients were retrospectively screened and 109 CRS patients with CC were enrolled. Lung function, Lund-Mackay Computed Tomography (CT) score, smoking status, peripheral blood eosinophil count, and immunoglobulin E concentration in serum samples, and Sino-Nasal Outcome Test were examined. Normal control subjects are also recruited. ResultsThe Forced Expiratory Volume in 1 second (FEV1.0), Percent Predicted FEV1.0, and FEV1.0/Forced Vital Capacity (FVC) ratio in the patients were significantly low as compared with the control subjects. The FEV1.0/FVC ratio was negatively correlated with the Lund-Mackay CT scores of the patients with a high CT score. ConclusionsThe CRS patients with CC should be investigated with lung function. In addition, the multidisciplinary evaluation including a pulmonologist is needed to manage the CRS patients with CC. Level of evidenceLevel 4.