This study aimed to elucidate the association between oral health status and chronic obstructive pulmonary disease (COPD) in Korean adults (≥ 40 years old) using a representative national dataset from the 6th Korea National Health and Nutrition Examination Survey (6th KNHANES, 2013-2015). Participants aged ≥ 40 years from the 6th KNHANES who had received an oral and pulmonary function tests (N = 7719) were included in this study. The participant characteristics according to COPD were compared using t-test and chi-squared test. Logistic regression analysis was used to estimate the association between oral health status and COPD. Participants with poor periodontal status exhibited a higher prevalence of COPD. Moreover, patients with COPD had a greater number of missing teeth than those without COPD. The logistic regression model adjusted for demographic, socioeconomic, health- and oral health-related factors showed that the periodontal status was not significantly associated with COPD, while participants with more missing teeth had a significantly increased possibility of having COPD. This study revealed that loss of teeth in adults aged ≥ 40 years was associated with COPD. © 2019 FDI World Dental Federation.