Purpose: This study investigated the relationship between linguistic and functional health literacy (HL) levels and the under- standing of chest computed tomography (CT) scan findings in patients with chronic obstructive pulmonary disease (COPD). Methods: This descriptive survey included 140 patients with COPD who regularly underwent chest CT scans and received explanations about the corresponding findings from pulmonologists at C University Hospital in Gwangju. Data were collected using structured questionnaires measuring general linguistic HL (Korean Health Literacy Assessment Tool, KHLAT), COPD-specific linguistic HL (COPD-related HL tool), and functional HL (Short Korean Health Literacy Scale, S-KHLS). Understanding of the chest CT findings was assessed using a tool developed by researchers based on explanations provided during outpatient consultations. Results: There were significant positive correlations between COPD-specific linguistic HL and understanding of chest CT findings (r=.37, p＜.001), and between functional HL and understanding of chest CT findings (r=.30, p＜.001). There was no significant correlation between general linguistic HL and understanding of chest CT findings (r=.10, p＜.232). Conclusion: HL was positively associated with understanding of chest CT finding...