Previous studies reported a robust relation between chronic obstructive pulmonary disease (COPD) and coronary artery disease (CAD). Systemic inflammation has been proposed as possible pathogenetic mechanism linking these 2 entities, although data on atherosclerotic coronary features in COPD patients are lacking. We studied atherosclerotic coronary plaque features in COPD patients presenting with acute coronary syndrome (ACS) using optical coherence tomography (OCT). ACS patients who underwent intracoronary OCT imaging of the culprit vessel were enrolled. Coronary plaque characteristics and OCT-defined macrophage infiltration (MØI) were assessed by OCT. ACS patients were divided into 2 groups according to the presence of an established diagnosis of COPD, and plaque features at the culprit site and along the culprit vessel were compared between the groups. Of 146 ACS patients (mean age:66.1 ± 12.7 years, 109 men), 47 (32.2%) had COPD. Patients with COPD had significantly higher prevalence of MØI (78.7% vs 54.5%, p = 0.005) and thin cap fibroatheroma (TCFA) (48.9% vs 22.2%, p = 0.001) at the culprit site. In the multivariate logistic regression, COPD was independently associated with MØI (odds ratio [OR] 21.209, 95% confidence interval [CI] 1.679 to 267.910, p = 0.018) and TCFA at the culprit site (OR 5.345, 95% CI 1.386 to 20.616, p = 0.015). Similarly, COPD was independently associated with both MØI (OR 3.570, 95% CI 1.472 to 8.658, p = 0.005) and TCFA (OR 4.088, 95% CI 1.584 to 10.554, p = 0.004) along the culprit vessel. In conclusion, in ACS patients who underwent OCT imaging of the culprit vessel, COPD was an independent predictor of plaque inflammation and vulnerability. These results may suggest that a higher inflammatory milieu in COPD patients might enhance local coronary inflammation, promoting CAD development and plaque vulnerability.