Obesity is a growing pandemic. Among obese patients with significant coronary artery stenosis, development of coronary collaterals was investigated. Consecutive 104 obese patients with stable angina pectoris were enrolled. Coronary collaterals were assessed according to the Cohen and Rentrop grading system and classified into 2 as those with poor collaterals (grade 0-1, Group 1) and those with good collaterals (grade 2-3, Group 2). Group I had higher body mass index, shorter duration of angina pectoris than Group 2. Poor collaterals were present in 82.3% and 59.5% of patients with and without (P = .019) metabolic syndrome, respectively. Metabolic syndrome score (sum of each component) was found to be negatively correlated with Rentrop score (r = -691; P < .001). After controlling for symptom duration and body mass index, metabolic syndrome kept independent association with poor collaterals among obese patients (P = .043, B = 1.8). Metabolic syndrome appears to influence the development of coronary collaterals among obese patients with stable coronary artery disease.