Background <p>Self-care adherence is crucial for COPD management, yet rates remain at 40%. E-health literacy and attitudes toward internet health information may influence self-care behaviors, but their associations with specific self-care components are unclear.</p> Aims <p>To examine associations between e-health literacy, attitudes toward internet health information, and self-care adherence components (maintenance, monitoring, management) in COPD patients.</p> Methods <p>This cross-sectional correlational study included 110 COPD patients recruited from a university hospital in the Republic of Korea. Participants completed validated instruments measuring e-health literacy, attitudes toward internet health information, and self-care adherence. Data were analyzed using descriptive statistics, correlation analysis, and stepwise multiple regression.</p> Results <p>Mean e-health literacy scores were 3.41 ± 0.74 (out of 5). Self-care adherence scores were 62.36 ± 17.39 (maintenance), 61.14 ± 24.07 (monitoring), and 56.12 ± 23.32 (management) out of 100. E-health literacy correlated with all self-care components (<i>r</i> = .46–0.59, <i>p</i> &lt; .001), as did attitudes toward internet health information (<i>r</i> = .45–0.66, <i>p</i> &lt; .001). E-health literacy was the strongest predictor of maintenance (β = 0.44) and monitoring (β = 0.45), while attitudes toward internet health information most strongly predicted management (β = 0.63). Models explained 27.4%-48.9% of variance.</p> Conclusion <p>Digital health competencies show differential associations with self-care components in COPD patients. E-health literacy primarily relates to routine self-care activities, while positive attitudes toward internet health information are crucial for symptom management responses. These findings support integrating digital health literacy assessments into COPD care.</p>