Angiopoietin-like protein 2 (Angptl2) is regarded as a proinflammatory factor in the pathogenesis of atherosclerosis and is expressed at high levels in patients with coronary artery disease. However, direct evidence of Angptl2 in acute coronary syndrome (ACS) is lacking. Our study was designed to investigate a possible relationship between serum Angptl2 and ACS.We evaluated 251 consecutive patients undergoing coronary angiography, consisting of 132 patients with ACS (unstable angina pectoris n = 60, acute myocardial infarction n = 72), 50 patients with stable angina pectoris, and 69 control patients. Serum Angptl2 concentration was measured in peripheral venous blood by an enzyme-linked immunosorbent assay.Serum Angptl2 levels were significant higher in patients with ACS than in those with stable angina (p0.05) or controls (p0.001). The difference between angplt2 levels in unstable angina and acute myocardial infarction subgroups was statistically insignificant (p = 0.831). In multivariable logistic regression models, using quartiles of Angptl2, Angptl2 was closely associated with ACS following adjustment of age, gender, established risk factors and high sensitivity C-reactive protein levels (odds ratio for quartile 4 vs. quartile 1: 10.182, 95% confidence interval 2.440-42.485, p = 0.001).Serum Angptl2 is a new candidate biomarker for risk stratification of ACS.