We investigated the association between coronary artery ectasia (CAE) and Neutrophil-to-lymphocyte ratio (NLR), an indicator of the inflammatory state. The study population included 434 patients (247 males, mean age 62 +/- 10 years) including 230 patients with isolated CAE and 104 patients with coronary artery disease and 100 patientss with normal coronary arteries. The NLR was measured at admission and 30 days after coronary angiography in all the patients. The NLR was significantly higher in patients with CAE than those with normal coronary arteries (2.2 +/- 0.6-1.3 +/- 0.6, P < .001). Linear regression analyses revealed that NLR (coefficient beta = -.61, P < .001) was significantly associated with severity of CAE. The NLR is significantly higher in patients with CAE compared to controls with normal coronary arteries, and NLR is associated with severity of CAE.