Elucidation of the underlying mechanisms of angiogenesis and arteriogenesis in coronary collateral formation is necessary for new therapies. Pleiotrophin is a secreted multifunctional cytokine and associated with the formation of functional cardiovascular neovascularization in a series of experimental animal models. We aimed to evaluate the serum levels of pleiotrophin in patients with chronic total coronary artery occlusion and poor or good collateral development. We included 88 consecutive patients (mean age of the entire population: 63.7±12.1 years, 68 male patients) with stable angina pectoris who underwent coronary angiography and had chronic total occlusion in at least one major coronary artery. Collateral grading was performed according to the Rentrop classification. After grading, patients were divided into poor collateral circulation (Rentrop grade 0 and 1) and good collateral circulation (Rentrop grades 2 and 3) groups. Serum pleiotrophin levels were measured using a commercial human ELISA kit. Fifty-eight patients had good and 30 patients had poor coronary collaterals. The good collateral group had higher serum pleiotrophin levels than the poor collateral group (690.1±187.9 vs. 415.3±165.9 ng/ml, P<0.001). Pleiotrophin levels were higher with higher Rentrop grade (P<0.001). In multivariate analysis, increased pleiotrophin was associated independently with good collateral development (odds ratio: 1.007; confidence interval: 1.003-1.012; P=0.002). This study showed that increased serum pleiotrophin levels are associated with better developed coronary collateral circulation. Further studies are needed to better understand the relationship.