The chronic systemic inflammation and oxidative stress are important features in chronic obstructive pulmonary disease (COPD). Atherosclerosis is accepted as an inflammatory disease. Both local and systemic inflammation and oxidative stress negatively affect the atherosclerotic process. Metabolic alterations, systemic inflammation, and neurohormonal activation frequently occur in patients with COPD. However, the impact of COPD on intensity and severity of atherosclerosis and morphology of stenotic lesions in patients with established coronary artery disease by coronary angiography is unknown. Eighty-eight patients who were diagnosed with COPD disease were enrolled in the study. Eighty-two patients without any pulmonary disease were included in the control group. Coronary angiography and blood gases analysis were performed in all patients. Gensini score and Extent score were used to evaluate the intensity and severity of atherosclerosis. Lesion morphologies were defined in all patients. The mean number of affected coronary arteries was 2.5 +/- 0.6 in the COPD group and 2.1 +/- 0.7 in the control group (P = 0.004). The mean Extent score was 37 +/- 16 in the COPD group and 23 +/- 11 in the control group (P = 0.001). The Gensini score in the COPD group was significantly higher than that in the control group (respectively 10.9 +/- 6.3 vs 6.6 +/- 4.1, P = 0.01). The number of critical lesions, and type B and C lesions were higher in the COPD group. Multivariate analysis demonstrated that COPD was independently predictive for Gensini score (odds ratio 1.371; 95% confidence interval 1.682-9.228; P = 0.002) and Extent score (odds ratio 1.648; 95% confidence interval 2.023-13.339; P = 0.001). Severity and intensity of atherosclerosis increases in COPD and atherosclerotic lesions have worse morphological properties in COPD.