This study aimed to investigate the quantitative high-resolution computed tomography (HRCT) characteristics of Preserved Ratio Impaired Spirometry (PRISm) and evaluate the correlation between HRCT parameters and pulmonary function parameters. The study included 94 cases with normal pulmonary function, 51 cases of PRISm, and 48 cases of mild to moderate chronic obstructive lung disease (COPD). The lung parenchyma, parametric response mapping (PRM), airway, and vessel parameters were measured by automatic segmentation software (AVIEW, Coreline Soft). Quantitative CT parameters showed mild to moderate correlation with pulmonary function parameters. The results revealed significant differences in small airway and vessel lesions between PRISm and normal pulmonary function subjects, with PRISm more inclined to mild to moderate COPD. The nomogram based on quantitative HRCT parameters demonstrated good predictive value for the early screening of PRISm, providing more objective evidence.