OBJECTIVES: The burden of COPD is increasing in Korea.Health-realted quality of life among COPD patients should be considered. Few national strategies to prevent and manage COPD have been intervened. In this study, we investigate the factors associated with COPD patients' quality of life. METHODS: : Data of Korean National Health and Nutrition Examination Survey(KNHANES) 2007-2012 were used. Multivariate regression anaysis was employed. Demographic variables (e.g. sex, age), socioeconomic status(SES) variables including education, insurance type, comorbidities(e.g. hypertension, diabetes, depressive disorder, cancer), severity of COPD, smoking were considered as independent variables. RESULTS: We found that female(beta=-0.0387, p<00001), age(beta=-0.0021,p<0.0001), Medical aid bebeficieries(beta=-0.1001,p<0.0001) showed a significantly lower score of EQ5D index. Mild(beta=0.2001, p<0.0001), moderate(beta=0.1982, p<0.0001), severe(beta=0.1765, p<0.0001) had significatly higher scores compared to that of very severe satge(GOLD IV). Education level also an important factor. Lower level of education(graduation from middle shcool or less) showed a negative association with EQ5D index score. Depression among comorbidities significantly worsened the quality of life of COPD paitents(beat=-0.7420, p<0.0001). Smoking status(current smoker, ex-smoker, non-skmoker) did not show a significant difference. CONCLUSIONS: Socio-economic status of COPD patients including sex, age, edication level and insurance type, were important factors related to the health-related quality of life. After controlling these factors, severe and depressive COPD patients reported their quality of life was significantly worsened. Strategies for COPD prevention and management should be developed and implemented. Improvement of health-related quality of life in COPD can be considered as an index of goals to achieve.